Answer:
x = 5
Explanation:
The small triangle has been dilated by 2 making it twice as big as before.
The side that measures 10 would be dilated by 0.5 to find x which is half a big.
10 x 0.5 = 5
Now check your work. On one side it asks 6x. So, 6 x 5 = 30. Since 30 is twice as much as 15. The rule applies that x = 5.
5 x 2 = 10
6 x 5 = 30
15 x 2 = 30