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20 votes
X^2 + 4x – 7 = 0
Pls n thx

User Pye
by
5.2k points

1 Answer

5 votes

Answer:

x = - 2 ±
√(11)

Explanation:

To solve the equation using the method of completing the square.

Given

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

x² + 4x = 7

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) ← exact solution

User Xzilla
by
4.4k points