Question

Which is the extraneous solution of (pic about to be posted)?

–5
–3
3
5

Answer 1

what is draco, and who is megan and who luv colin

Answer 2

square both sides

Answer 3

ok

Answer 4

-x = √ (2x + 15)
(-x)^2 = ( √ (2x + 15) ) ^2
x^2 = 2x + 15
x^2 - 2x - 15 = 0
(x - 5) ( x + 3) = 0
Zero Product Property
x = 5 or x = -3

5 is the extraneous root because if 5 is substituted into the original equation:
-5 = √ (2(-5) + 15)
Immediately, you see that the square root cannot equal a negative number.
These "extra" roots that are not true solutions of the original radical equation are called extraneous roots and are rejected as answers.