Solve x2+6x=7 by completing the square.Which is the solution set of the equation?

Mathematics

1 answer:

NARA [144]3 years ago

4 0

Answer:

x = - 7, x = 1

Step-by-step explanation:

Given

x² + 6x = 7

To complete the square

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

x² + 2(3)x + 9 = 7 + 9

(x + 3)² = 16 ( take the square root of both sides )

x + 3 = ± $\sqrt{16}$ = ± 4 ( subtract 3 from both sides )

x = - 3 ± 4

x = - 3 - 4 = - 7

x = - 3 + 4 = 1

Solution set = { - 7, 1 }

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