Question

the value of ( 89 square - 79 square ) is __________

Answer 1

89^2 - 79^2 = (89+79)(89-79) = 168*10 = 1680

Hope it helps

Answer 2

$89 \times 89 = 7921 \\ 79 \times 79 = 6241 \\ 7921 - 6241 = 1680$