Answer:
x=15
Step-by-step explanation:
This is an Isosceles Triangle, so that means there are two angels that are the same. So we could rearrange the equations to get:
[tex]3x=5x-30\\\text{ subtract 5x on both sides }\\\\-2x=-30\\\text{ divide by two on both sides }\\x=15\\[/tex]
Hope it helps.
