It is a similar triangle so the side length of the smaller triangle (x and x-2) are in the same ratio as the bigger triangle (2x+5 and 2x-1). As the ratio is the same, you can equate them and solve for x.
0.5 is the first way
1/2 is the second way
50% is the third way.
Hope that helps bud :).
I think the answer is {-4,1,5,8}
Is it D? if not i’m so sorry