Answer:
x=5
Explanation:
Put everything on one side of the equation and have it equal to 180 degrees.
13x+3+72+8x= 180
Combine like terms
21x+75= 180
Subtract 75 on both sides
21x = 105
Divide by 21 on both sides
x= 5
hope this helped!
4.5m questions
5.9m answers