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X squared + 2x is equal to 7 ​

1 Answer

1 vote

Answer:

x = - 1 ± 2
√(2)

Explanation:

x² + 2x = 7

solve using the method of completing the square

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

x² + 2(1)x + 1 = 7 + 1

(x + 1)² = 8 ( take square root of both sides )

x + 1 = ±
√(8) = ± 2
√(2) ( subtract 1 from both sides )

x = - 1 ± 2
√(2)