Question

Can anyone send working of this please ?

Answer 1

The parallel lines create similar triangles. Which means sides are proportional...

`(BR)/(CS) = (AR)/(AS)`

`(BR)/(CS) = (10)/(14) = (5)/(7)`
So if then the ratio of AR to AS = 5/7
Create a proportion with the other similar triangle that contains the shared side:

`(5)/(7) = (e)/(18)`
Cross multiply
e =
`(90)/(7)=12 (6)/(7)`