Answer: x = 9
Explanation:
Add the three angles up, and equal them to 180, as a triangle has 180*.
(13x + 2) + (3x - 4) + (5x - 7) = 180
Add together the like terms.
13x + 3x + 5x = 21x
2 + (-4) + (-7) = 9
21x + 9 = 180
21x = 189 (subtract 9 from both sides)
x = 9 (divide 21 from each side)
