Answer:
15y^2 -1
Step-by-step explanation:
(7y^2+y-7)+(8y^2-y-6)
15y^2-1
15y²-13
(7y²+y-7) +(8y²-y-6)
=7y²+y-7+8y²-y-6
=7y²+8y²+y-y-7-6
=15y²-13
