Solve for b
b=2
b=-2
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b^{2}\times 9+b^{2}+8=b^{2}\left(b^{2}+8\right)
Variable b cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by b^{2}\left(b^{2}+8\right), the least common multiple of 8+b^{2},b^{2}.
10b^{2}+8=b^{2}\left(b^{2}+8\right)
Combine b^{2}\times 9 and b^{2} to get 10b^{2}.
10b^{2}+8=b^{4}+8b^{2}
Use the distributive property to multiply b^{2} by b^{2}+8.
10b^{2}+8-b^{4}=8b^{2}
Subtract b^{4} from both sides.
10b^{2}+8-b^{4}-8b^{2}=0
Subtract 8b^{2} from both sides.
2b^{2}+8-b^{4}=0
Combine 10b^{2} and -8b^{2} to get 2b^{2}.
-t^{2}+2t+8=0
Substitute t for b^{2}.
t=\frac{-2±\sqrt{2^{2}-4\left(-1\right)\times 8}}{-2}
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. Substitute -1 for a, 2 for b, and 8 for c in the quadratic formula.
t=\frac{-2±6}{-2}
Do the calculations.
t=-2 t=4
Solve the equation t=\frac{-2±6}{-2} when ± is plus and when ± is minus.
b=2 b=-2
Since b=t^{2}, the solutions are obtained by evaluating b=±\sqrt{t} for positive t.
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