Solve x2-4x-7=0 by completing the square

x = 2 ±

Step-by-step explanation:

Given

x² - 4x - 7 = 0 ( add 7 to both sides )

x² - 4x = 7

To complete the square

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

x² + 2(- 2)x + (- 2)² = 7 + (- 2)²

(x - 2)² = 7 + 4 = 11 ( take the square root of both sides )

x - 2 = ± ( add 2 to both sides )

x = 2 ± ← exact solutions

n

step-by-step explanation:

answer: a

step-by-step explanation: