
Ratio problem
The measure of two supplementary angles are in a ratio 3:15. What are the measures of the angles? And can you explain what method you used to do this because at the moment i got 1/5=? I don't know what to plug in on the other side along with an x to evaluate this.

Let $\displaystyle \alpha,\,\beta$ be the angles. So $\displaystyle \alpha=k,\,\beta=5k.$ ($\displaystyle k$ is a positive constant.) Besides, you know that $\displaystyle \alpha+\beta=180^\circ.$
Go on from there.

wow im dumb cant believe i never thought of that. thanks