Answer:
2n - 4.
Step-by-step explanation:
(n+8) + (n−12)
= n + 8 + n - 12
= n + n + 8 - 12
= 2n - 4.
2n-4
add like terms. n+n=2n 8+-12=-4
They are quadrilaterals that have opposite sides equal in length.
