When CA= 3x-1 and SR=5x+4, what is CA?

Answer:
CA=17
Step-by-step explanation:
From given picture we see that A and C are the mid points of sides QR and QS respectively.
We know that line joining mid points of the two sides of triangle is always half of the length of the third side.
So that means:
2*CA=SR
2(3x-1)=5x+4
6x-2=5x+4
6x-5x=4+2
x=6
plug value of x into CA=3x-1
CA=3*6-1=18-1=17
Hence final answer is CA=17