Answer:
Step-by-step explanation:
Im going to assume they want x+108.
You have 2 expressions sitting on a line, so when added to each other they must = 180
So add and set up an equality
x+108+x+78=180
Combine like terms
2x+186=180
Solve
2x+186=180
-180 -180
2x+6=0
-6 -6
2x=-6
________
2
x=-3
Substitute X for -3
-3+108=
105.
