We know that with a straight line, the resulting angle is 180. So, knowing this: 6x+12+5x+3=180 Solve for x 11x+15=180 11x=165 x=15 Plug x back into your respective angles Angle 1: 6(15)+12=102 degrees Angle 2: 5(15)+3=78 degrees Therefore angle 2 is 78 degrees.
