Question

find the measure of the missing angle.

Explanation:

Step1: Recall angle - sum property of a triangle

The sum of the interior angles of a triangle is 180°. In a right - triangle, one angle is 90°. Let the missing angle be $x$.

Step2: Set up the equation

We know that for a triangle with angles 90°, an unknown angle $x$, and another given non - right angle, the sum of the angles is 180°. So, $x + 90^{\circ}+$ (the given non - right angle) $=180^{\circ}$.
However, since the given non - right angle is not provided in a way that can be used in a calculation from the image description clearly. Assuming this is a right - triangle and we know the sum of interior angles of a triangle is 180°. If we assume the non - right angle adjacent to the missing angle is $\theta$, then the missing angle $x = 180^{\circ}-90^{\circ}-\theta$.
If we assume the non - right angle is calculated from the side lengths using trigonometry (but side lengths are not relevant for angle - sum property here), and we just focus on the angle - sum property of a triangle. If we assume the non - right angle shown in the context of the problem (not clearly defined in the image text but if we consider the problem as a basic right - triangle angle - finding problem) is some known value. Let's assume the non - right angle is $\alpha$. Then $x=180^{\circ}-90^{\circ}-\alpha = 90^{\circ}-\alpha$.
If we assume the non - right angle related to the problem is 26° (from the image elements that seem to be angle values), then:
$x=180^{\circ}-90^{\circ}-26^{\circ}$

Step3: Calculate the missing angle

$x = 64^{\circ}$

Answer:

$64^{\circ}$