Converting angles in Radians to degrees

Question

convert following angles to degrees. Give your answer correct to 2 decimal points.

a) $-3.5$

$-3.5 \times \dfrac{180}{π} = ?$

i'm stuck on this stage..

Answer 1

$\pi=3.141592653...$ is a constant (it's just a number).

Type this into a calculator and you're done.

To convert radians to degrees: multiply by $\frac{180}{\pi}$.

To convert degrees to radians: multiply by $\frac{\pi}{180}$.

So $-3.5 \times \frac{180}{\pi}= -200.535228296...$, which is $$\boxed{-200.54 \ ^\circ}$$ to two decimal places.

Answer 2

We have, via the definition, that $$\pi\,\text{rad}=180^\circ\Rightarrow 1\,\text{rad}=\frac{180}{\pi}^\circ,$$ and also $$1^\circ=\frac{\pi}{180}\text{ rad}.$$