Question

Solve the equation by completing the square x^2-18x+58=0. is it

Answer 1

To complete the square we add a constant (23) so that the constant on the left is (18/2)² = 81.
   x² -18x +58 +23 = 23
   (x -9)² = 23 . . . . . . . . . . . rewrite the left side as a square
   x -9 = ±√23 . . . . . . . . . . . take the square root
   x = 9 ±√23 . . . . . . . . . . . .add 9

The answer corresponds to selection ...
   D. x = 9 ±√23