4x^2=16

Completing the square

Easier to just solve, but anyway

if you insist on completint the square

4x^2+0x=16

(4x^2+0x) = 16

4 (x^2+0x) = 16

0/2=0, 0^2=16

4 (x^2+0x+0-0) = 16

4 ((x+0) ^2-0) = 16

4 (x+0) ^2-0=16

4 (x+0) ^2=16+0

4 (x+0) ^2=16

divide both sides by 4

(x+0) ^2=4

sqrt both sides don't forget to take positive and negative roots

x+0=+/-2

minus 0 from both sides

x=+/-2-0

x=+/-2

x=2 or - 2