In ΔKLM, m∠K = (6x−1)∘, m∠L = (7x+13)∘, and m∠M = (x+0)∘. Find m∠L.

Answer 1

well, you know that the angles must add up to 180°, so

6x-1 + 7x+13 + x = 180

find x, then m∠L = 7x+13.