ILL GIVE BRAINLY PLEASE HELP

Answer:
x=3
Step-by-step explanation:
Figure ABCD is a rectangle. In rectangles, opposite sides are equal. In the figure, BC and AD are opposite of each other, therefore their side lengths are equal. The side lengths are given: BC=9x-6, and AD=3x+12. Write this as an equation:
please let me know if this is wrong, hope it helps :)