(x-5)(2y+4)-(x-5)(4y+1) Помогите решить)

Question

(x-5)(2y+4)-(x-5)(4y+1)
Помогите решить)

Answer 1

(x-5)(2y+4)-(x-5)(4y+1)=2xy+4x-10y-20-(4xy+x-20y-5)=2xy+4x-10y-20-4xy-x+20y+5=-2xy+3x+10y-15