How do i find the possible values of x

The 2 triangles in the big triangle are similar so we can write
3x / 3x - 2 = 5x / 3x 

9x^2 =  15x^2 - 10x
6x^2 - 10x = 0
x(6x - 10) = 0
x= 0 or  5/3

Ihad to look for the figure and here is my answer:

based on the given circle d with angles adc and arc ac, here is how we are going to look for the measure of angle abc:
arc ac=angle adc
8x-8=7x+2
8x-7x=2+8
x=10
< adc=7(10)+2=72
< abc=72/2=36
so the answer for this is 36 degrees.