(2в-3)(5в+7)+21

To simplify the given expression (2в-3)(5в+7)+21, we need to apply the distributive property.

First, multiply the terms inside the brackets:

(2в-3) * 5в = 10в^2 - 15в (2в-3) * 7 = 14в - 21

Next, combine the results:

(10в^2 - 15в) + (14в - 21) + 21 = 10в^2 - 15в + 14в - 21 + 21 = 10в^2 - v

Therefore, the simplified expression is 10в^2 - v.