Question

упрости выражения

2b(x+3y)
5a(a+5-2b)
6x(-3a-7b+3)

Answer 1

$2b(x+3y)=2bx+6by\\\\5a(a+5-2b)=5a^2+25a-10ab\\\\6x(-3a-7b+3)=-18ax-42bx+18x$

Answer 2

$\sf 2b\cdot(x+3y)=2b\cdot x+2b\cdot 3y=2bx+6by~;\\5a\cdot(a+5-2b)=5a\cdot a+5a\cdot5-5a\cdot2b=5a^2+25a-10ab~;\\6x\cdot(-3a-7b+3)=-6x\cdot3a-6x\cdot7b+6x\cdot3=-18ax-42bx+18x.$