Question 940650
{{{3n+9-(n/3)^2=-8}}}
{{{3n+9-n^2/9=-8}}}
{{{9(3n+9-n^2/9)=-8*9}}} Multiply both sides by 9
{{{27n+81-n^2=-72}}}  Add 72 to each side
{{{27n+81-n^2+72=-72+72}}}
{{{27n+153-n^2=0}}}  Multiply by -1 and rearrange
{{{n^2-27n-153=0}}}  Solve the quadratic *[invoke quadratic "n", 1, -27, -153]
(n-31.8)(n+4.8)=0
n=31.8, -4.8098
CHECK:
Solution 1:
{{{3n+9-(n/3)^2=-8
{{{(3*31.8)+9-(31.8/3)^2=-8
{{{(95.4+9)-(112.36)=-8}}}
(((114.4-112.36)=-8
           2.04=-8  FALSE. Not a solution
Solution 2:
{{{3n+9-(n/3)^2=-8}}}
{{{3(-4.8098)+9-(-4.8098/3)^2=-8}}}
{{{(-14.429+9)-(-1.6)^2=-8}}}
{{{-5.429-2.57=-8}}}
        -7.999=-8 This is the solution

The number is =-4.8098