Answer:
10
Explanation:
These are similar triangles, which means that the ratio between 16 to 8 will equal x+10 to x. This could be written out as 16/8 = x+10/x. 16/8 is 2, which means that x+10 is twice the amount of x. We can write this out as 2x = x+10. We can then simplify this and get x = 10