How do you solve $9a=-a²-18$ ?

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Answer 1 · 2016-05-29T22:09:18

$a=-3$ , and $a=-6$ .

Start bringing everything on the same side changing the sing when you "jump" the $=$ symbol.

$a^2+9a+18=0$

Now you can use the formula for the second order equation

$a=(-9\pmsqrt(81-4*18))/2=(-9\pmsqrt(9))/2=(-9\pm3)/2$ .
The solution with the $+$ is
$a=-3$
and the solution with the $-$ is
$a=-6$ .

How do you solve 9a=-a²-18 9a=-a²-18?