Completeing the square and square root property?

Question

Complete the square show all work:
x^2+6x+1=0

Solve using square root property
2x^2-35=15

Square root property
(x+6)^2=4

Answer 1

x^2 + 6x + 1 = 0
x^2 + 6x = -1
half of 6 is 3, 3 squared is 9:
x^2 + 6x + 9 = -1 + 9
(x + 3)^2 = 8
x + 3 = +/- √8
x = -3 +/- 2√2

2x^2 - 35 = 15
2x^2 = 50
x^2 = 25
x = +/- √25
x = +/-5

(x + 6)^2 = 4
x + 6 = +/-√4
x = -6 +/-2
x = -4, -8