100x**+1-20x = (10x-1)**
x+4y**+4x**y = (x**+2y)**
1+81y**-18y = (1-9y)**
8ab***+16a**+b = (4a+b***)**
100x**+1-20x = (10x-1)**
x+4y**+4x**y = (x**+2y)**
1+81y**-18y = (1-9y)**
8ab***+16a**+b = (4a+b***)**