Answer:
im pretty sure what u have ther is right
4y^(2)+14y+31
Step-by-step explanation:
First you need to do (y+7)(y+7)
y^2+7y+7y+49
y^2+14y+49
Add it all together
y^2+14y+49+3y^2-15
It will be 3 because its take away hope this helped