Question

1. Multiply.
a. (2x + 3y)(3y - 4x)​

Answer 1

$(2x + 3y)( - 4x + 3y) \\ = 2x( - 4x + 3y) + 3y( - 4x + 3y) \\ = - 8 {x}^{2} + 6xy - 12xy + 9 {y}^{2} \: \: \: \: \: \: \: \: \: \\ = - 8 {x}^{2} - 6xy + 9 {y}^{2} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \boxed{ \orange{\boxed{= 9 {y}^{2} - 8 {x}^{2} - 6xy}} \: \: \green{✓}} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$

Answer 2

Answer:

2x(3y-4x)+3y(3y-4x)

2x×3y+2x×4x+3y×3y-3y×4x

6xy+8x2+9y2-12yx

9y2-8x2-6xy