Question

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

A.x = 4+ 13
B.X= 4+13
C.x= 4+19
D.X=4 + √19

Answer 1

`x = -4 \pm √(19)`

Explanation:

Let us put 3 on the right side and rewrite the equation as

`x^2 + 8x = 3`

By putting 16 on both sides, our equation becomes

`x^2 + 8x + 16 = 3 + 16 = 19`

`\Rightarrow (x + 4)^2 = 19`

Taking the square root of the equation, we get

`x + 4 = \pm √(19)`

Finally, solving for x,

`x = -4 \pm √(19)`