Answer:
(a) x = -7, 1
Explanation:
In most cases, it is useful to follow the directions. This can be solved easily by completing the square.
Completing the square
The square is completed by adding the square of the x-term coefficient to both sides.
x² +6x +9 = 7 +9 . . . . . add 9
(x +3)² = 16 . . . . . . . . simplify . . . . write the left side as a square
The square is now complete. We finish the solution by taking the square root.
x +3 = ±√16 = ±4 . . . . take the square root
x = -3 ±4 . . . . . . . . . subtract 3
x = -7, 1