I think that you have missed to upload the picture of the triangle so the necessary details to solve the question are missing.
I searched your question from the internet and found the picture as attached below.
In this triangle, J is mid point of GH.
K is mid point of HF.
Then JH=GH/2 or 2JH=GH
KH=FH/2 or 2KH=FH
angle JHK and angle GHF are common
since ratios of corresponding sides as shown above is same and we are getting one common side then the triangles GHF and JHK are similar.
Then ratio or correspondng sides of the triangles must be equal. We get:
[tex] \frac{GH}{JH}=\frac{GF}{JK} [/tex]
[tex] \frac{2JH}{JH}=\frac{5y+3}{2y+5} [/tex]
[tex] 2=\frac{5y+3}{2y+5} [/tex]
2(2y+5)=5y+3
4y+10=5y+3
4y-5y=3-10
-y=-7
y=7
Hence final answer is y=7.
