So the longer lines are 2x longer than the shorter lines
Look at line segment BD
40 is 2x as long as 9x+2
In order to make the equation true, multiple 9x+2 by 2
So, you should get:
40=18x+4
36=18x
x=2
Plug the 2 into 19X+14, and divide that answer by 2, because GF is 2x smaller than AG
19x+14
19(2)+14
52
52/2=26
Hope this helps!!