36/x+6 + 36/x-6=9/2
<=> 2.36(x-6)/2(x+6)(x-6) + 2.36(x+6)/2(x+6)(x-6) = 9(x+6)(x-6)/2(x+6)(x-6)
=>72(x-6) + 72(x+6)=9(x+6)(x-6)
<=> 72x-432+72x+432= 9(x^2-6^2)
<=>144x=9x^2-324
<=>144x-9x^2=-324
<=>9x(16-x)=-324
<=>9x=-324 hoặc 16-x=-324
<=>x=-36 <=>x=340