Question

Which of the following correctly completes the square for the equation

below?
x2 + 4x = 27
A. (x + 2)2 = 31
B. (x + 2)2 = 43
C. (x + 4)2 = 31
D. (x+4)2 = 43
SUBMI
PREVIOUS

Answer 1

A. (x + 2)^2 = 31.

Explanation:

x^2 + 4x = 27

x^2 + 4x - 27 = 0

A. (x + 2)^2 = 31

x^2 + 4x + 4 - 31 = 0

x^2 + 4x - 27 = 0

This option corresponds to the given equation, so it is correct.

B. (x + 2)^2 = 43

x^2 + 4x + 4 - 43 = 0

x^2 + 4x - 39 = 0

This does not correspond to the equation.

C. (x + 4)^2 = 31

x^2 + 8x + 16 - 31 = 0

x^2 + 8x - 15 = 0

This does not correspond to the equation.

D. (x+4)^2 = 43

x^2 + 8x + 16 - 43 = 0

x^2 + 8x - 27 = 0

This does not correspond to the equation.

So, your answer is A. (x + 2)^2 = 31.

Make sure to SUBMIT and check your PREVIOUS answers to make sure they are right! XD Also, hope this helps!