Answer:
n=6/5 or n=-2
Step-by-step explanation:
7n^2+16n+15=2n^2+3
collect like terms
7n^2-2n^2 +16n=3-15
5n^2 + 16n= -12
5n^2 +16n + 12
(5n^2+10n)+(6n+12)
5n(n+2)+6(n+2)
(5n+6)(n+2)
