Question

Упростите выражение (3m-7n)²-9m(m-5n)

Answer 1

(3m-7n)^2-9m (m-5n)=9m^2-49n^2-9m^2-45mn=-49n^2-45mn

Answer 2

$(3m - 7n) {}^{2} - 9m(m - 5n) = 9 {m}^{2} - 49 {n}^{2} - 9 {m}^{2} + 45mn = - 49 {n}^{2} + 45mn$