x = 10
The triangles are similar by SAS, so we can set up a proportion of their sides.
9/(33-9) = 12/(3x+2)
9/24 = 12/3x+2
Reduce
3/8 = 12/3x+2
Cross multiply
3(3x+2) = 12*8
Distribute and multiply
9x + 6 = 96
Subtract 6
9x = 90
Divide by 9
x = 10
Check:
9/24 = 12/3x+2
9/24 = 12/3*10 + 2
9/24 = 12/30 + 2
9/24 = 12/32
3/8 = 3/8 :)
