Question

Y-1 = square root y+5

What value of y is a solution to the equation above?

Answer 1

y = 4

Explanation:

y - 1 = √y + 5

(y - 1)² = y + 5 (Square both sides)

y² - 2y + 1 = y + 5 (Expand left side)

y² - 3y - 4 = 0 (Subtract y and 5 from both sides)

(y + 1) (y - 4) = 0 (Factor)

y = -1, 4 (Use ZPP)

When we check y = -1 we see that it is not a solution so the answer is y = 4.