Question

find the measure of the missing angle.

Explanation:

Step1: Recall angle - sum property

The sum of angles in a triangle is $180^{\circ}$.

Step2: Identify known angles

We have a right - triangle with angles $90^{\circ}$ and $40^{\circ}$.

Step3: Calculate the missing angle

Let the missing angle be $x$. Then $x=180^{\circ}-90^{\circ}-40^{\circ}=50^{\circ}$.

Answer:

$50^{\circ}$