How do you solve the equation $2 x^{2} + 16 = x^{2} + 7$ $2x^2+16=x^2+7$ ?

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Answer 1 · 2017-07-26T19:43:47

Not Real

Combine like terms:
$2 x^{2} + 16 = x^{2} + 7$ $2x^2+16=x^2+7$
$x^{2} = - 9$ $x^2 = -9$
Solve for x by taking the square root of both sides.
$\sqrt{x^{2}} = \pm \sqrt{- 9}$ $sqrt(x^2)=+-sqrt(-9)$
The answer is not real, because you are taking the square root of a negative number. Nonetheless, the answer would be...
$x = \pm 3 i$ $x=+-3i$

How do you solve the equation 2x2+16=x2+72x^2+16=x^2+7?