Given that cm, cm, cm, and cm, find the value of .
Given several coplanar parallel lines and two transversals, the lengths of the corresponding segments on the transversals are proportional. This means that . Use this fact to solve for as follows:
If the value of were 0, the lengths of both and would be cm, and the lengths of both and would be a negative number of centimetres. This is impossible, so the value of is 7.