Answer:
x=7
Step-by-step explanation:
The angles will always add up to 180.
Subtract 76 from 180, giving you 104
So now, your other two angles when added together equals 104.
104=5x+6+8x+7
Add your like terms, so add 5x and 8x to give you 13x, and add 6 and 7 to give you 13. Subtract 13 from both sides, leaving you with 91=13x
Divide 13 from both sides, giving you 7=x
Now plug in the 7 for the x for the original expressions. So 5x+6= 5×7+6
5×7=35+6=41
8x+7=8×7+7
8×7=56+7
56+7=63
