Question

Найдите значение выражения (6b-9)(9b+6)-9b(6b+9) при b=5,3

Answer 1

(6b-9)(9b+6)-9b(6b+9) = (6*(2)-9)*(9*(2)+6)-9*(2)*(6*(2)+9) = -301

b = 5.3 = 126 b

126 * 5.3 - 54 = 667.8 + 54 = - 721.8

Answer 2

$\displaystyle (6b-9)(9b+6)-9b(6b+9)=54b^2-81b+36b-54-54b^2-81b=$
$\displaystyle = -126b-54$
b=5.3
$\displaystyle -126*5.3-54= -667.8-54=-721.8$