Vertical angles practice

1 answer

What is the measure of angle A in the following diagram?

\begin{align*}
\angle A &= 90^{\circ} \\
\angle B &= 90^{\circ} \\
\angle C &= 90^{\circ} \\
\angle D &= 90^{\circ}
\end{align*}

Answer: 90°