Two angles in a vertical pair have measures that add to 70° . What is the measure of each angle?

Answer 1

Let $x$ be the measure of the first angle in the pair, and let $y$ be the measure of the second angle. Since the angles are vertical angles, they have the same measure, so $x=y$. We are told that the measures of the angles add to $70^\circ$, so $x+y=70^\circ$. But then $x+y=70^\circ$ is the same as $x+x=70^\circ$, so $2x=70^\circ$. Dividing both sides of this equation by 2 gives $x=\boxed{35^\circ}$, which means $y$ also equals $\boxed{35^\circ}$.

Answer 2

What happened there?