Respuesta :

(2x +y)(5x-y+3)

10x^2 - 2xy + 6x + 5xy - y^2 + 3y

10x^2 -2xy+5xy + 6x - y^2 + 3y
 
10x^2 +3xy + 6x -y^2 +3y        

Looking at the answer boxes the sign looks wrong to me from y^2 ( a negative times a positive is a negative) I may be wrong. 

Anyone else?