Answer:
x=11
Basic fact:
Angles in a triangle add up to 180 degrees
Step-by-step explanation:
so let's gather all the information we have been given
3x+28+5x+52+2x-10
now let's add everything up
3x+5x+2x=10x
28+52-10=70
we know that 10x+70 =180
-70 from both sides
10x=110
divide by 10 to get x on its own
x=11
