Answer:

Step-by-step explanation:
The formula is 
<em>We need to solve for
, so we can perform the steps shown below:</em>

Hence, the third answer choice is correct.
Answer:
-1.75.
Step-by-step explanation:
The z-score = (n - m) / d where n is the value (13) m = mean and d = standard deviation.
= (13 - 20) / 4
= -1.75 (answer)
Answer:
x = 2, x = - 2
Step-by-step explanation:
Step 1:
x² - 4 = 0 Equation
Step 2:
x² = 4 Add 4 on both sides
Step 3:
x =
Square 4
Answer:
x = 2, x = - 2
Hope This Helps :)
The answer is BAD. Hope this helps