y(y+1)=135
=> y2+y-135=0
=> y2+y+\(\frac{1}{4}\) - \(\frac{541}{4}\)=0
=> (y+\(\frac{1}{2}\))2-( \(\frac{\sqrt{541}}{2}\))2=0
=> (y+\(\frac{1}{2}\)-\(\frac{\sqrt{541}}{2}\))(y+\(\frac{1}{2}\)+\(\frac{\sqrt{541}}{2}\))=0
=> y =\(\frac{\sqrt{541}-1}{2}\), y =- \(\frac{\sqrt{541}+1}{2}\)
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