I: a triangle has a total of 180 degrees. So, we can find the other angle in the triangle by subtracting 180-110= 70 degrees. A straight line has a total of 180 degrees, also. So we can set up another equation that says 180=2m+70. When we simplify, we get 110=2m. Solve, and we get m=55.
J: we can do the same thing in reverse. A straight line has 180 degrees. So we can find the unlabeled angle in the triangle by solving 180=120+a. a=60. Then, we also know that the sum of the angles in the triangle is 180. So, we can set up the equation 180=60+5x. Subtract 60 from both sides and get 120 is 5x. Divide by x, and you get x=24.
