Answer:

Step-by-step explanation:
Given

Required
Find

Calculate 
Using tan rule

So:






'
'So:



Answer:
True, they may not be congruent
Step-by-step explanation:
A figure cannot be determined as congruent from three angles alone. In order for two shapes to be congruent, all corresponding parts must be congruent. This means all the sides and angles of the two shapes must be the same in order for the two shapes to be congruent. If we know all the angles are the same, the sides could still be different lengths, so this does not prove congruency.
Answer:
20:50
Step-by-step explanation:
2:5
They got 20 by multiplying 2 by 10 so we multiply 5 by 10 which is 50