Question

2(x+2)^2+6=18
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x=?
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Answer 1

Răspuns:

Explicație pas cu pas:

$2(x+2)^{2} + 6 = 18\\2(x^{2} + 4x + 4) + 6 = 18\\2x^{2} + 8x + 8 + 6 = 18\\2x^{2} + 8x + 14 = 18\\2x^{2} + 8x = 18 - 14\\2x^{2} + 8x = 4\\2(x^{2} + 4x) = 4\\x^{2} + 4x = 4 : 2\\x^{2} + 4x = 2$

$x*(x + 4) = 2\\x = 2 sau (x + 4) = 2\\\\x = 2 \\x + 4 = 2\\x = 2 - 4\\ x = -2$

Solutia ecuatiei este S = {-2;2|