log3(x-1)=log9(x+5)
=1/2 * log3(x+5)
=log3(x+5)^1/2
=log3√(x+5)
所以x-1=√(x+5)
(x-1)^2=x+5
接下来就可以解啦,有什么不理解的在线联系^_^