Three I think. Might be wrong
Your answers would be c and d because angles across from the exterior angle are equal to it
Given, y varies directly as x
So,

Where c is a constant
When y equals 5 when x is 8
So,

So, the relation between y and x

now , when x = 9
Substitute with x to find y

So, the answer is option 2. y = 45/8
Answer:
If the triangle is similar by any axiom then the ratio of their sides will be equal then you can easily find the side of the triangle
OR
You can also find it by congurency.
Hope this helps
2x + 8 would be the simplified version of this question