Respuesta :

F stands for first: the first term times are 5y and 3y respectively, 5y*3y=15y²
O stands for outside: 5y*(-1)=-5y
I stands for inside: (-4)*(3y)=-12y
L stands for last: (-4)*(-1)=4
add them up: 15y²+(-5y)+(-12y)+4=15y²-17y+4 is the answer.