Answer:
Step-by-step explanation:
in a triangle, the sum of all angles is 180 (angle sum theorem). so use the equation 180=50+80+10x. then solve
1. combine like terms
it becomes 180=130+10x
2. subtract 130 from both sides
it becomes 50=10x
3. divide both sides by 10
it becomes 5=x
so, x=5
hope this helped :)
