Question

20) Find angle Dd= 54.9 cm, f= 69.2 cm, F = 56°

Answer 1

Using sine rule formula to resolve the value for angle D

The sine rule formula is,

`(sinD)/(d)=(sinF)/(f)`

Given:

`\begin{gathered} d=54.9cm \\ f=69.2cm \\ F=56^0 \end{gathered}`

Therefore,

`(sinD)/(54.9)=(sin56^0)/(69.2)`

Simplify

`\begin{gathered} sinD=(54.9* sin56^0)/(69.2)=0.65771911464 \\ D=sin^(-1)(0.65771911464)=41.12615063003\approx41^0(nearest\text{ degree\rparen} \\ D=41^0 \end{gathered}`

Hence, the answer is

`\angle D=41^0`