Question

Solve x2 + 8x − 3 = 0 using the completing-the-square method.

Answer 1

Answer:

x = -4 ±√19. See below for the steps of the method.

Step-by-step explanation:

It can work well to add the opposite of the constant before you start.

... x² +8x = 3

Now, you identify the x-coefficient (8) and add the square of half that: 4² = 16. This addition completes the square.

... x² +8x +16 = 3 +16

Rewrite as a square.

... (x +4)² = 19

Now take the square root and subtract 4.

... (x +4) = ±√19

... x = -4 ±√19 . . . . . . . the solution by the desired method