Answer:
x=7
Explanation:
As seen from the higher two numbers, there is a distinct ratio between the shorter side and the longer side. To find the ratio we simply get the given two without the x and we get 8:12 which simplifies to 2:3 or 1: 1.5
This means in order to find 3x-6, we need to multiply 10 by 1.5 which means:
3x-6=15
3x=21
x=7
Hope this helped!