Question

(2b+5)²-(2b-3)(3b+5)​

Answer 1

Ответ:

$(2b + 5) {}^{2} - (2b - 3)(3b + 5) = 4b {}^{2} + 20b + 25 - (6b {}^{2} + 10b - 9b - 15) = 4b {}^{2} + 20b + 25 - 6b {}^{2} - b + 15 = - 2b {}^{2} + 19b + 40.$

Объяснение:

★ (a+b)²=a²+2ab+b² ★