Question

Solve for x.

2x^2 − 11 = 21

x= or x=

(both x= need to be answered)

Answer 1

x = 4 or x= -4

Explanation:

2x^2 − 11 = 21

Add 11 to each side

2x^2 − 11+11 = 21+11

2x^2 = 32

Divide by 2

2x^2 /2 = 32/2

x^2 = 16

Take the square root of each side

sqrt(x^2) = sqrt(16)

x = ± 4

x = 4 or x= -4