Not sure if this is what you need
Answer:
30
Step-by-step explanation:
45+45 = 90
150-90 = 60
60/2 = 30
I think...
Ok, so we know that RST is equal to 6x+12
And RST is also equal to 78 + 3x-12
so we set them equal to each other
6x + 12 = 3x - 12 + 78
And simplify
3x = 54
x = 18
Finally, we solve for the angle with 18 for x
6(18) + 12
108 + 12
120
Hope this helps
