116k views
4 votes
I need help with this practice I attempted this previously my answer is in the box

I need help with this practice I attempted this previously my answer is in the box-example-1
User Dilini
by
5.9k points

1 Answer

4 votes

Step-by-step explanation

Since we have the △CDE,let's represent the triangle:

We can apply the law of sines to get the value of the angle C, and then by the Sum of Interior Angles of a Triangle Theorem, we can get the value of the angle D as shown as follows:


(\sin C)/(DE)=(\sin E)/(CD)

Substituting terms:


(\sin C)/(5)=(\sin 83)/(12)

Isolating sin C:


\sin C=5\cdot(\sin 83)/(12)

Applying sin^-1 to both sides:


C=\sin ^(-1)(5\cdot(\sin 83)/(12))

Computing the terms:


C=\sin ^(-1)(0.4135)

Computing the argument:


C=24.43\text{ degre}es

Finally, by applying the Sum of Interior Angles of a Triangle Theorem, we can get the value of D as shown as follows:

C + D + E = 180

24.43 + D + 83 = 180

Isolating D:

D = 180 - 83 - 24.43

Subtracting numbers:

D = 72.57 ≈ 72.6 degrees

I need help with this practice I attempted this previously my answer is in the box-example-1
User TinyRacoon
by
6.1k points