Answer:
(x) = 
Step-by-step explanation:
let y = 2x
Rearrange making x the subject
divide both sides by 2
= x
changing y back into terms of x
(x) = 
-10x=-12x + 21 + 11
-10x= -12 + 32
-10x + 12x = 32
2x = 32
X = 32/2
Answer:
the probability when the IQ is lower than 136 is 0.9641
Step-by-step explanation:
Given that
The mean is 100
The standard deviation is 20
We need to find out the probability when the IQ is lower than 136
So,
z value equivalent to 136 = (136 - 100) ÷ 20 = 1.8
Now
p (z < 1.8) = 0.9641
hence, the probability when the IQ is lower than 136 is 0.9641
Answer is B.) (-3,-3) and (2,7)