Question

In △CDE , CD=12 , DE=5 , and m∠E=83∘ . What is m∠D to the nearest tenth of a degree?

Answer 1

Answer:

As law of sin:

CD/sinE = DE/sinC

Then

12/sin83 = 5/sinC

Then

sinC = 5*sin83/12 = 0.413

Then

C = arcsin(0.413) = ~24.4 deg

Then

D = 180-C-E = 180-83-24.4 = ~72.6

Hope this help, bro!