Answer:
3b-10=20
Step-by-step explanation:
3b-10=20
3b-10+10=20+10
3b=30
3b/3=30/3
b=10
Step-by-step explanation:
I think we are missing some information (angle F or B or a side length would be great).
but just the right angles are not enough to calculate specific numbers. they would depend on the angle F or e.g. the side length of AB.
without any further information F and AB can be freely changed without changing the known facts, but it changes also C, B, G
so, all I can say is C = 180 - B.
and that G = B.
