Question 129847
(a+b)^2=a^2+2ab+b^2

so 

sqrt(2x-5)+sqrt(9+x)=13

2x-5+2sqrt(2x-5)sqrt(9+x)+9+x=169

3x+4+2sqrt(2x-5)sqrt(9+x)=169

3x-165 = -2sqrt(2x-5)sqrt(9+x)

(3x-165)^2=4(2x-5)(9+x)

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