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SOLVE THE EQUATION BY COMPLETING THE SQUARE!!!!! HELPPPPPPPPPP!!!!!!!!!!!

SOLVE THE EQUATION BY COMPLETING THE SQUARE!!!!! HELPPPPPPPPPP!!!!!!!!!!!-example-1
User Quantme
by
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1 Answer

2 votes

Answer:

x ≈ - 5.32, x ≈ 1.32

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 + 4 = 7 + 4

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

x + 2 = ±
√(11) ( subtract 2 from both sides )

x = - 2 ±
√(11)

Hence

x = - 2 -
√(11) ≈ - 5.32

x = - 2 +
√(11) ≈ 1.32

User Richi
by
6.1k points