Question

The quadrilaterals JkLM and PQRS are similar.find the length x of QR.

Answer 1

3/4.8=4/x
3x=19.2
x=6.4

Answer 2

Two quadrilaterals are similar if corresponding sides taken in the same sequence (even if clockwise for one quadriateral and counterclockwise for the other) are proportional and corresponding angles taken in the same sequence are equal in measure.
If the quadrilaterals JKLM and PQRS are similar, then


`(JK)/(PQ) = (KL)/(QR) = (LM)/(RS) = (JM)/(PS)`.
Hence

`(4)/(QR) = (3)/(4.8) = (5)/(8) = (3)/(4.8)` and

`QR= (4\cdot 8)/(5) =6.4`.