(2а+5)²=(2а)²+2×2а×5+5²=4а²+20а+25
(а-4х)²=а²-2а×4х+4х²=а²-8ах+16х²
(4у+7)²=(4у)²+2×4у×7+7²=16у²+56у+49
(10х-3)²=(10х)²-2×10х×3+3²=100х²-60х+9
(2а+5)²=(2а)²+2×2а×5+5²=4а²+20а+25
(а-4х)²=а²-2а×4х+4х²=а²-8ах+16х²
(4у+7)²=(4у)²+2×4у×7+7²=16у²+56у+49
(10х-3)²=(10х)²-2×10х×3+3²=100х²-60х+9