1) What is the equivalent of this?

Question

-5x(2x+7y)+7xy-4x(y+3)

Answer 1

just expand, then collect like terms

= -10x^2 - 35xy + 7xy - 4xy - 12x
= -10x^2 -32xy - 12x
or
= -2(5x^2 + 16xy + 6x)