(4-y)²=y²-8y+16
1) (y-7)²=y²-14y+49
2) (4a+3b)²=16a²+24ab+9b²
3) (a-4)(a+4)=a²-16
4) (5m+6n)(6n-5m) =30mn-25m²+36n²-30mn=-25m²+36n²=36n²-25m²
(4-y)²=y²-8y+16
1) (y-7)²=y²-14y+49
2) (4a+3b)²=16a²+24ab+9b²
3) (a-4)(a+4)=a²-16
4) (5m+6n)(6n-5m) =30mn-25m²+36n²-30mn=-25m²+36n²=36n²-25m²