Answer:

Step-by-step explanation:
Given


Required

First, calculate 
We have:

This gives:

Substitute 


Substitute 



Split

This gives

Answer:
180+54sqrt3
You have to use the formula that is contained within the lessons, the answer you should have before you format it like this is: 273.530743609
Answer:
m<A = 30 degrees.
Step-by-step explanation:
m < C in triangle ABC = m < C in EDC so
x + 13 + 42 + x + 13 = 180
2x = 180 - 13 - 13 - 42
2x = 112
x = 56.
So m < C = 56+13 = 69.
m < B = m < D = 81
M < A = 180 - 69 - 81
= 180 - 150 = 30.