Answer:
x = ± 10
Step-by-step explanation:
Given
x² - 100 = 0 ( add 100 to both sides )
x² = 100 ( take the square root of both sides )
x = ± 
← note plus or minus, hence
x = ± 10
Answer:
2x4y=2... hope this helps.
Answer: Biased sample
Step-by-step explanation:
This is a biased sample because only students with strong opinions are likely going to volunteer or show interest in representing the school at the board meeting. This sample is a voluntary type sample, and at such the conclusion is not valid. This sample is biased because a group or population of students have a higher or lower sampling probability.
Answer:
15 x 1 + 5 x 3 = 30
Step-by-step explanation:
If you turn the x into a one then it multiplies 15 by one and then it remains at 15, then you multiply 5 and 3 so that's 15 and then 15 + 15 is 30.
Answer:
{-2,10}
Step-by-step explanation:
x^2 - 8x = 20
Take the coefficient of x
-8
Divide by 2
-8/2 =-4
Square it
(-4)^2 =16
Add this to each side
x^2 - 8x+16 = 20+16
x^2 - 8x+16 = 36
The left hand side becomes( x + (-8/2) )^2
(x - 4)^2 = 36
Take the square root of each side
sqrt((x - 4)^2) =±sqrt( 36)
x-4 = ±6
Add 4 to each side
x-4+4 = 4±6
x = 4±6
x = 4+6 x = 4-6
x = 10 x = -2
