Đáp án:$\left \{ {{x=1} \atop {y=20}} \right.$
Giải thích các bước giải:
$\left \{ {{\frac{(x+3)(y+3)}{2}-\frac{xy}{2}=36} \atop {\frac{xy}{2}-\frac{(x-2)(y-4)}{2}=26}} \right.$⇔ $\left \{ {{(x+3)(y+3)-xy=72} \atop {xy-(x-2)(y-4)=52}} \right.$⇔ $\left \{ {{3x+3y=63} \atop {4x+2y=44}} \right.$⇔ $\left \{ {{x+y=21} \atop {2x+y=22}} \right.$⇔ $\left \{ {{x=1} \atop {y=20}} \right.$