x(9x+9)=270

Multiply the terms inside the parentheses by x:

 

9x² + 9x = 270

 

Divide all terms by 9

x² + x = 30

 

Subtract 30 from both sides

x² + x - 30 = 0

 

This factorises

(x + 6)(x - 5) = 0

 

So x = -6 and x =5 are the two possible solutions

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