12.
What is the solution of the equation x2 + 2x - 7 = 0?
Answers
Answer:
cancel out as much of the equation as possible by doing inverse operations so add the 7 to both sides
x2 + 2x = 7
Divide by 2
x2 = 3.5
divide by 2 again
x = 1.75
now change x with 1.75 to check
1.75 x 2 = 3.5
3.5 + 3.5 - 7 = 0 so 1.75 is correct
Hope this helps
Step-by-step explanation:
Related Questions
The stem-and-leaf plot displays data collected on the size of 15 classes at two different schools.
Mountain View School Seaside School
0 5, 8
9, 8, 2, 0 1 0, 1, 2, 5, 6, 8
8, 7, 6, 5, 5, 4, 4, 3, 1, 0 2 5, 5, 7, 7, 8
0 3 0, 6
Key: 2 | 1 | 0 means 12 for Mountain View and 10 for Seaside
Part A: Calculate the measures of center. Show all work. (2 points)
Part B: Calculate the measures of variability. Show all work. (1 point)
Part C: If you are interested in a smaller class size, which school is a better choice for you? Explain your reasoning. (1 point)
Answers
For Mountain View School:
Data: 0, 0, 0, 0, 1, 2, 3, 4, 4, 5, 5, 5, 5, 6, 7, 8, 8, 8, 9
Mean: (0 + 0 + 0 + 0 + 1 + 2 + 3 + 4 + 4 + 5 + 5 + 5 + 5 + 6 + 7 + 8 + 8 + 8 + 9) / 19
= 100 / 19
≈ 5.26
To find the median, we need to arrange the data in ascending order: 0, 0, 0, 0, 1, 2, 3, 4, 4, 5, 5, 5, 5, 6, 7, 8, 8, 8, 9.
The median is the middle value, which is the 10th value in this case.
Median: 5
For Seaside School:
Data: 0, 0, 0, 1, 1, 2, 2, 4, 5, 5, 5, 5, 6, 7, 7, 8, 8, 8, 9
Mean: (0 + 0 + 0 + 1 + 1 + 2 + 2 + 4 + 5 + 5 + 5 + 5 + 6 + 7 + 7 + 8 + 8 + 8 + 9) / 19
= 80 / 19
≈ 4.21
To find the median, we need to arrange the data in ascending order: 0, 0, 0, 1, 1, 2, 2, 4, 5, 5, 5, 5, 6, 7, 7, 8, 8, 8, 9.
The median is the middle value, which is the 10th value in this case.
Median: 5
Now let's calculate the measures of variability, specifically the range and interquartile range (IQR).
Range: The range is the difference between the largest and smallest values in the dataset.
For Mountain View School:
Range: 9 - 0 = 9
For Seaside School:
Range: 9 - 0 = 9
Interquartile Range (IQR): The IQR is the difference between the third quartile (Q3) and the first quartile (Q1) and measures the spread of the middle 50% of the data.
For Mountain View School:
Q1 = 3
Q3 = 7
IQR = Q3 - Q1 = 7 - 3 = 4
For Seaside School:
Q1 = 2
Q3 = 7
IQR = Q3 - Q1 = 7 - 2 = 5
To determine which school is a better choice for a smaller class size, we can consider both the mean and the median.
Both the mean and median for Mountain View School are higher than those for Seaside School. This suggests that, on average, the class sizes at Mountain View School are larger than those at Seaside School. Therefore, if you are interested in a smaller class size, Seaside School would be a better choice
For Mountain View School:
- Median: The median class size is the middle value, which is 25.
- Mean: The mean class size is the sum of all the class sizes divided by the total number of classes, which is (29 + 28 + 28 + 27 + 25 + 24 + 24 + 23 + 21 + 20 + 19 + 18 + 15 + 13 + 10) / 15 = 21.27.
For Seaside School:
- Median: The median class size is the middle value, which is 20.
- Mean: The mean class size is the sum of all the class sizes divided by the total number of classes, which is (25 + 25 + 27 + 27 + 28 + 28 + 28 + 30 + 31 + 35 + 36 + 38 + 40 + 43 + 45) / 15 = 31.13.
Part B:
For Mountain View School:
- Range: The range is the difference between the largest and smallest values, which is 29 - 10 = 19.
- Interquartile Range (IQR): The IQR is the difference between the third quartile (Q3) and the first quartile (Q1). From the stem-and-leaf plot, we can see that Q1 is 20 and Q3 is 28. Therefore, the IQR is 28 - 20 = 8.
For Seaside School:
- Range: The range is the difference between the largest and smallest values, which is 45 - 25 = 20.
- Interquartile Range (IQR): The IQR is the difference between the third quartile (Q3) and the first quartile (Q1). From the stem-and-leaf plot, we can see that Q1 is 27 and Q3 is 38. Therefore, the IQR is 38 - 27 = 11.
Part C:
If you are interested in a smaller class size, Mountain View School is a better choice for you because it has a lower mean and median class size than Seaside School.
In the function F(t) = 50(1.274, what is the rate of change?
O A. 2% decay
O B. 20% decay
O C. 20% growth
O D. 2% growth
Answers
Answer:
c
Step-by-step explanation:
math
Please hurry!!!!!!!!!! I'll give you a brainliest if you answer first
it is the picture
Answers
Answer:
Graph 3 is not a function
Step-by-step explanation:
We can use the vertical line test to determine if it is not a function. If a vertical line passes through the graph more than once, it is not a function.
A vertical line will pass through graph 3 twice, so it cannot be a function.
-12x-3=-51 what is answer
Answers
Answer:
x = 4
Step-by-step explanation:
-12x - 3 = -51
=> First add 3 to each side:
-12x = -48
=> Now divide each side by -12
x = 4
Hope this helps!
(5 x 4) x 2 = 5 x (4 x 2), Identify the Property of Operation that is being used.
Identity Property
Associative Property
Commutative Property
Distributive Property
Answers
Answer: Commutative
Step-by-step explanation: Even though there are different numbers in the parentheses, it gives the same answer.
Kevan earns a net salary of $55,670 per year and pays a tax rate of 21%. How much income tax does Kevan pay?
Answers
Compare the wait times in the box plot.
(Please note that I just need the help with the IQR part.)
Answers
Answer:
Step-by-step explanation: S = 6-12
These are your time rage's
W = 8-14
subtract both ranges 12-6 and 14-8 are both 6 so ur IQR time is 6
I believe this correct, hope this helps
10POINTS !!
the sum of the length of a side of two squares is 18cm and the sum of their areas is 212 cm^2. find the length of a side of the smaller square
Answers
Step-by-step explanation:
lengtha + b = 18cm
a = 18 - b
Areaa² + b² = 212cm²
(18-b)² + b² = 212
324 - 36b + b² + b² = 212
2b² - 36b + 112 = 0
b² - 18b + 56 = 0
b² - 4b - 14b + 56 = 0
b(b-4) -14(b - 4) = 0
(b-4) (b-14) = 0
b-4 = 0 OR. b-14 = 0
b = 4 cm b = 14 cm
so 4cm < 14cm
so , length of a side of the smaller square is 4cm .......
And , large square's = 14cm .....
Answer:
square one sides = 14, 14
square 2 sides = 4, 4
14 + 4 = 18
14 x 14 + 4 x 4 = 212
Step-by-step explanation:
14 x 14 + 4 x 4
this is the area of the 2 being added
the sides lengths are 14 and 4
Please help! I’ll give brainliest!!!
Answers
can someone find the area of this rectangle please?x
Answers
Answer:
72 cm^2
Step-by-step explanation:
If the Length is twice the Width, then W = W and L = 2W.
The perimeter formula is P = 2W + 2L, which here is:
36 = 2W + 2(2W), or
36 = 2W + 4W = 6W; then W = 6 and L = 12.
The area formula is A = L * W, which here is:
A = 6*12 = 72 cm^2
How do I answer this and what theorem do I use? (Geometry)
Answers
If 2 tangents are drawn to a circle from the same exterior point, they are congruent. So TR = WR, which means that 7k - 19.4 = 48.5. Solving for k gives you 9.7 for k
Part I: Making the Race
Henri is Emile's younger brother and they are having a walking race. Emile can walk 2.5 meters per second whereas Henri walks 1 meter per second. Because Emile is faster, they give Henri a 45 meter head start. Emile knows Henri would enjoy winning the race, but they do not want to make the race so short that it is obvious Emile let Henri win.
1. How long should the race be so that Henri will win in a close race?
2. Describe or show your strategy on how you came up with your answer for #1.
Answers
Answer:
Step-by-step explanation:
To make the race close, the length of the race should be 450 meters.
Here's the reasoning behind the answer:
Let's first calculate how long it would take for Emile to catch up to Henri, assuming Henri starts 45 meters ahead.
The time it takes Emile to cover the same 45-meter distance is 45/2.5 = 18 seconds.
During this time, Henri would have walked a distance of 1 x 18 = 18 meters.
So, after 18 seconds, Emile will have caught up to Henri and will be 27 meters ahead of him (45 - 18 = 27).
To make the race close, we want Henri to finish just a split second before Emile. So, we can assume that Henri will finish the race just as Emile catches up to him.
Let's call the total distance of the race "d."
So, Henri will walk d meters, while Emile will walk d + 27 meters (the 27 meters is the distance Emile has to walk after catching up to Henri).
We can set up an equation to solve for d:
d/1 = (d + 27)/2.5
Solving for d, we get:
d = 450
So, the race should be 450 meters long for Henri to win in a close race.
help? (question = image below)
Answers
Answer:
horizontal, left, right, x-, down
Step-by-step explanation:
I guess im smart
.
Which of the following measures would create an infinite number of triangles?
two sides of 4 cm and 7 cm with an angle of 54° between them
three sides: 3 cm, 5 cm, and 7 cm
three angles: 62°, 34°, and 84°
three sides: 3 cm, 5 cm, and 10 cm
Answers
Answer: The three angles choice.
Step-by-step explanation:
First we need to remove the measures that can't create a triangle.
3, 5, 10 cm sides.
First of all, This is impossible. 3+5=8, which means that 10 is too large of a side to create a triangle.
Now the other ones can either create one or infinite.
Two sides: 4, 7 cm and angle 54 between them.
tan(54) = o/7 ; o = 7(tan(54)) = 9.63
OR
tan(54) = o/4 ; o = 4(tan(54)) = 5.5
There are two possible triangles, but not infinite.
3, 5, 7 ; The parameters work, but there's only one possible triangle here.
The three angles can create infinite number of triangles, since there's an infinite number of side lengths that can fit these angle proportions.
Answer: The three sides one.
Step-by-step explanation: hope this helps! <3
Find the missing values in the ratio table. Then write the equivalent ratios.
Answers
The missing values of the above ratio table are
1. 1 cake
1. 20 pies
2. 2 cakes
3. 25/3 pies
1)Given : 3 cakes = 5 pies
then, 1 cake = 5/3pies
2) 12 cakes = 12 × 5/3
= 20 pies
3) 10/3 × 3/5 = 2 cakes
4) 5 × 5/3 = 25/3 pies
Learn more about Ratio and Proportions at
brainly.com/question/13513438
the answer is 1 for the remaining box in cakes
What is the definition of a infinitely many solution equation
Answers
Answer:
Normally infinity means something that never ends, something that has no end, it goes on forever.
Step-by-step explanation:
I don’t actually know if this is right, but in math infinitely means something that goes on forever.
Find d, the depth of the water
Answers
Answer:
d=27 ft
Step-by-step explanation:
U need use Thales's theorem:
height of smaller triangle (15)divide by side (40) is eaqul to height of bigger triangle (d) divide by side (72).
\(\frac{15}{40} =\frac{d}{72} \\40*d=15*72\\d=\frac{15*72}{40} \\d=27\)
Priya and Han are biking in the same direction on the same path.
a. Han is riding at a constant speed of 16 miles per hour. Write an expression that shows how many miles Han has gone after t hours.
b. Priya started riding a half-hour before Han. If Han has been riding for t hours, how long has Priya been riding?
c. Priya is riding at a constant speed of 12 miles per hour. Write an expression that shows how many miles Priya has gone after Han has been riding for t hours.
d. Use your expressions to find when Han and Priya meet.
Answers
Answer:
a) \(H=16t\)
b) \(t+0.5\)
c) \(P=12(t+0.5)\)
d) They meet 1.5 hours after Han started riding.
Step-by-step explanation:
Check out https://brainly.com/question/14025233 for more steps!Triangle FGH has vertices F(−3, 2), G(1, 3), and H(−1, −1). Triangle F′G′H′ has vertices F′(3, 2), G′(−1, 3), and H′(1, −1).
Which transformation of triangle FGH produced triangle F′G′H′?
A)a rotation of 90° counterclockwise around the origin
B)a rotation of 90° clockwise around the origin
C)a reflection across the y-axis
d)a reflection across the x-axis
Answers
D) a reflection across the x-axis (y=0)
Solve rational Equation
Please Show Full Steps Please!
Answers
Answer:
x=1
Step-by-step
Step 1:
Simplify x/x2
Dividing exponential expressions :
1.1 x1 divided by x2 = x(1 - 2) = x(-1) = 1/x1 = 1/
Equation at the end of step 1:
2 1 1
(((—+1)-—)-1)-((2•—)-1) = 0
x x x
STEP 2:Rewriting the whole as an Equivalent Fraction:
2.1 Subtracting a whole from a fraction
Rewrite the whole as a fraction using x as the denominator :
1 1 • x
1 = — = —————
1 x
Equivalent fraction : The fraction thus generated looks different but has the same value as the whole
Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator
Adding fractions that have a common denominator :
2.2 Adding up the two equivalent fractions
Add the two equivalent fractions which now have a common denominator
Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:
2 - (x) 2 - x
——— = ———
x x
Equation at the end of step 2:
2 1 (2-x)
(((—+1)-—)-1)-————— = 0
x x x
STEP 3:
Simplify 1/x
Equation at the end of step 3:
2 1 (2 - x)
(((— + 1) - —) - 1) - ——————— = 0
x x x
STEP4:
Simplify: 2/x
Equation at the end of step 4:
2 1 (2 - x)
(((— + 1) - —) - 1) - ——————— = 0
x x x
STEP 5:
Rewriting the whole as an Equivalent Fraction :
5.1 Adding a whole to a fraction
Rewrite the whole as a fraction using x as the denominator :
1 1 • x
1 = — = —————
1 x
Adding fractions that have a common denominator :
5.2 Adding up the two equivalent fractions
2 + x x + 2
————— = —————
x x
Equation at the end of step 5:
(x + 2) 1 (2 - x)
((——————— - —) - 1) - ——————— = 0
x x x
STEP 6:Adding fractions which have a common denominator :
Adding fractions which have a common denominator
Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:
(x+2) - (1) x + 1
——————————— = —————
x x
Equation at the end of step 6:
(x + 1) (2 - x)
(——————— - 1) - ——————— = 0
x x
STEP 7:
Rewriting the whole as an Equivalent Fraction :
7.1 Subtracting a whole from a fraction
Rewrite the whole as a fraction using x as the denominator :
1 1 • x
1 = — = —————
1 x
Adding fractions that have a common denominator :
7.2 Adding up the two equivalent fractions
(x+1) - (x) 1
——————————— = —
x x
Equation at the end of step 7:
1 (2 - x)
— - ——————— = 0
x x
STEP 8:
Adding fractions which have a common denominator :
8.1 Adding fractions which have a common denominator
Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:
1 - ((2-x)) x - 1
——————————— = —————
x x
Equation at the end of step 8:
x - 1
————— = 0
x
STEP 9:
When a fraction equals zero :
9.1 When a fraction equals zero ...
Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.
Now,to get rid of the denominator, Tiger multiplys both sides of the equation by the denominator.
Here's how:
x-1
——— • x = 0 • x
x
Now, on the left hand side, the x cancels out the denominator, while, on the right hand side, zero times anything is still zero.
The equation now takes the shape :
x-1 = 0
.2 Solve : x-1 = 0
Add 1 to both sides of the equation :
x = 1
One solution was found :
x = 1
Need Help, Pleaseeeeeeeee.
Answers
5.6^-5 • 5.6^3
And the exponents would go like -
-5 + 3 = -2
5.6^-2
3.4^-4 • 3.4^-7
-4 + -7
3.4^-11
5.6^-2 • 3.4^-11
Answer: D
I'LL GIVE BRAINLIEST!!
( True / False ) Force is used in aristocracy.
If true how?
If false why?
Answers
Answer:
true
Aristocracy is a form of government in which political power is held by a select few privileged people called aristocrats or nobles. Coming from a Greek word meaning “rule by the best,” aristocrats are considered the most qualified to rule because of their moral and intellectual superiority.
Last year, the Golden State Warriors won 50 games. This year, they won 15 games. Which proportion represents the percent decrease in the amount of games the Golden State Warriors won?
Answers
Answer:
So, if there's an answer that's 30 that'd be it.
Step-by-step explanation:
15 + 30 = 50 therefore you add it up.
In a right triangle, the length of one leg is 20 units. The length of the other leg is 12 units. What is the length of the hypotenuse?
Answers
a^2+b^2=c^2
about 23.3238
Answer:
2.2
Step-by-step explanation:
i got 100%
8TH GRADE MATH 100 POINTS+BRAINLIEST - Factor Quadratic equations- please write out the steps, explain simply, and possibly provide a couple rules to remember for questions like these in the future. Any offensive answers or ones for the sake of points will be reported THANKS SO MUCH!!!
Also, 5 more 8th grade math questions are coming–GIVING AWAY 600 POINTS
Answers
Hello,
We have : (a + b)² = a² + 2ab + b²
4x² + 20x + 25 = (2x)² + 2 × 2x × 5 + 5² = (2x + 5)² → answer B
Here, we have a = 2x and b = 5 !
Answer:
\(\textsf{b.} \quad (2x+5)^2\)
Step-by-step explanation:
Given quadratic equation:
\(4x^2+20x+25\)
To factor a quadratic in the form \(ax^2+bx+c\), find two numbers that multiply to \(ac\) and sum to \(b\).
\(\implies ac=4 \times 25=100\)
\(\implies b=20\)
Factors of 100 that sum to 20: 10 and 10
Rewrite \(b\) as the sum of these two numbers:
\(\implies 4x^2+10x+10x+25\)
Factorize the first two terms and the last two terms separately:
\(\implies 2x(2x+5)+5(2x+5)\)
Factor out the common term (2x + 5):
\(\implies (2x+5)(2x+5)\)
Simplify:
\(\implies (2x+5)^2\)
Learn more about quadratic equations here:
https://brainly.com/question/27997764
Pls help, it’s not 6
Answers
Answer:
then its probaly 5
Step-by-step explanation:
The linear functions f(x) and g(x) are represented on the graph, where g(x) is a transformation of f(x):
A graph with two linear functions; f of x passes through 5, 0 and 10, 10, and g of x passes through negative 3, 0 and 2, 10.
Part A: Describe two types of transformations that can be used to transform f(x) to g(x). (2 points)
Part B: Solve for k in each type of transformation. (4 points)
Part C: Write an equation for each type of transformation that can be used to transform f(x) to g(x). (4 points)
Answer:
honestly i dont know give me a minute ill re edit this
Step-by-step explanation:
Find the commission.
Answers
Answer:
63.9
Step-by-step explanation:
Convert 9% to a decimal: 0.09
710×.09=63.9
Please give me brainliest
i need help.........................
Answers
Answer:
y is located at (1,1)
the measure is 56
c - congruent
Step-by-step explanation:
If its rotated at its vortex then its rotating around the coordinates of Y
If the angle is rotated then the value of the angle does not change
Allen uses the claw part of a hammer to remove a nail from a piece of wood. This lever does not make Allen stronger, but it helps him to complete the task using less force.Explain how this lever works.
Answers
Answer:The lever operates by applying forces at different distances
Step-by-step explanation:
Which of the following is a solution to the equation 3 - 4y = 19?
Answers
Answer:
y= -4
Step-by-step explanation:
Equation: 3-4y= 19
Step 1: subtract 3 from both sides of the equation.
3-3-4y =19 -3
The 3's cancel out on the left side and on the right side you are left with 16.
Step 2: divide both sides by -4.
-4y÷-4= 16÷ -4
The -4's cancel out on the left side and on the right side you are left with -4.
y= -4
Answer:y=-4
Step-by-step explanation:
3-4y=19 Step One: subtract 3 on both sides to remove 3 on the left
-4y=16 Step Two: divide each side by negative 4 to leave y on it's own
y=-4 Your answer
Very easy, hoped this helps! :)