Find the roots of the quadratic function by completing the square: x^2 + 4x - 1 = 0

x = - 2 ±

Step-by-step explanation:

Given

x² + 4x - 1 = 0 ( add 1 to both sides )

x² + 4x = 1

To complete the square

add (half the coefficient of the x- term )² to both sides

x² + 2(2)x + 2² = 1 + 2² ← complete the square on the left side

(x + 2)² = 5 ← take the square root of both sides

x + 2 = ± ← subtract 2 from both sides

x = - 2 ±

roots are x = - 2 - or x = - 2 +

location: point 0

step-by-step explanation:

well, -8 to 10 on a number line is 18 spaces.

1/9 of 18 is 2.

so, 4/9 of 18 must be 8.

8 spaces from -8 (a) is 0.

so, 4/9 of the way from -8 to 10 is 0!