1. find the value of x in the equation √ x + 5 = √ x + 45.
a. 16
b. 4
c. 1
d. 2

I think you mean
sqrt x + 5 = sqrt (x+45)

if you plug in x = 4,
left side = sqrt 4 + 5 = 2+ 5 = 7

right side = sqrt (4+45) = sqrt 49 = 7

so the answer is x = 4 :)