Extraneous Solutions What is the solution set for the equation: x+2=square root 4x+13

Question

A{-3,3}

B{2}

C{-2,3}

or

D{3}

Answer 1

x + 2 = √ (4x + 13)

Square both sides to get x² + 4x + 4 = 4x + 13

x² - 9 = 0

(x + 3)(x - 3) = 0

x = 3 or -3

-3 is extraneous (i.e., it doesn't check in the original equation)

3 does check

So, x = 3

Answer 2

I'm assuming 4x + 13 is under the radical sign.

-3 + 2 = -1 and square roots aren't negative, so A is out.

Keep going.