Answer:
a = 1/2 (1 ±sqrt(47))
Step-by-step explanation:
a^2-a+12=0
We will complete the square
Subtract 12 from each side
a^2-a+12-12=0-12
a^2-a=-12
The coefficient of a = -1
-Divide by 2 and then square it
(-1/2) ^2 = 1/4
Add it to each side
a^2 -a +1/4=-12 +1/4
(a-1/2)^2 = -11 3/4
(a-1/2)^2= -47/4
Take the square root of each side
sqrt((a-1/2)^2) =sqrt(-47/4)
a-1/2 = ±i sqrt(1/4) sqrt(47)
a-1/2= ±i/2 sqrt(47)
Add 1/2 to each side
a-1/2+1/2 = 1/2± i/2 sqrt(47)
a = 1/2± i/2 sqrt(47)
a = 1/2 (1 ±sqrt(47))
Answer:
(-2 , 5)
(-1 , 0)
(1 , -4)
(3 , 0)
(4 , -5)
Step-by-step explanation:
<u>First solve the equation:</u>
x² - 2x - 3
<em><u>Find two numbers with have a sum of -2 and a product of -3.</u></em>
-3 and 1
(x - 3)(x + 1)
Solve for x:
x - 3 = 0
x = 3
x + 1 = 0
x = -1
You know that the graph will cross the x-axis at -1 and 3.
(-1 , 0)
(3 , 0)
You know that the graph is positive.
<u>Complete the square to find the vertex</u>
x² - 2x - 3
(x - 1)² = x² - 2 + 1
x² - 2x - 3 = x² - 2 + 1 - 2 = (x - 1)² - 2
1 = 0
x = 1
Substitute into the original equation:
x² - 2x - 3 =
1² - (2 * 1) - 3 =
1 - 2 - 3 =
-4
(1 , -4)
<em><u>You can input any two numbers within -10 and 10. Such as -2 and 4.</u></em>
x² - 2x - 3 =
-2² - (2 * -2) - 3 =
4- -4- 3 =
5
(-2 , 5)
x² - 2x - 3 =
4² - (2 * 4) - 3 =
16 - 8 - 3 =
-5
(4 , -5)
Answer:
B. 97%
Step-by-step explanation:
20 students is -2 standard deviations away from the mean
35 is +3 standard deviations away from the mean
100 - 2.4 = 97.6
(2.4 is amount of data we are not using)
please refer to the standard deviation graph attached :)
Answer:
Calculate Mean Absolute Deviation (M.A.D)
Step-by-step explanation:
To find the mean absolute deviation of the data, start by finding the mean of the data set.Find the sum of the data values, and divide the sum by the number of data values.Find the absolute value of the difference between each data value and the mean: |data value – mean|.
