X decreased by the square of nine
x - 9^2 = x - 81
Isolate the variable by dividing each side by factors that don't contain the variable.
f=e-g/d
You should get it now from my previous answer.
But to apply it.
9 - 8b + 6b
9 + (-8b + 6b) <- Collect like bases (b)
9 + (-2b)
9 - 2b
Therefore it simplified is 9 - 2b
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