In a cross line problem, one part of the cross, (such as 63°) is always the same on the other side. (like y+23° and 63°. This means Y=40 because 40+23 is 63.
To find x, you must know that 360° is all the way around in degrees. you know that 126° (63 +63) is already taken up. So you subtract 126 from 360 and then multiply the answer by 1/2 because you trying to find the bottom total.(360-126)=234(1/2)= 117 Lastly, you find X in the equation 2x-17=117.
