The quadrilaterals shown are labelled as similar, and one has been dilated to reflect as the other. In quadrilateral P, the side labelled 4 is similar (or equivalent to) to the side labelled 5 in quadrilateral Q. Therefore the dilation factor that makes P become Q is 5/4. This means every side in quadrilateral P is multiplied by 5/4 to derive the dimension of the similar side in Q.
Likewise, the factor that dilates Q into P is given as 4/5. Therefore;
(1) The scale factor of the dilation that takes P to Q is 5/4
(2) The scale factor of the dilation that takes Q to P is 4/5
