Question

(2х-5)(3х+4)=
(х-3y)(2y+5x)=
a(a-5)-(a-2)(a-3)=
(2n+1)(4n^2-2n+1)

Answer 1

1) 6x^2+11x-20
2) 2xy+5x^2-6y^2-15xy= 5x^2-6y^2-13xy
3)a^2-5a-a^2+3a+2a-6=-6
4)8n^3+1