First things first is to find what line QP corresponds with which is line MN
After that you find what multiplied into 5 would make it 2. The easiest way of ding so is to divide 2 by 5 which is 0.4. Now you want to find what line PR corresponds with which is OM. Now you multiply 4 (length of line OM) by 0.4 to find the length of line PR which is x. So now line PR is equal to 1.6 and x. Which also means that x=1.6
