Find the measure of the unknown angle.85.6°112.8°89.9°?

The sum of the angles in a quadrilateral (a shape with four sides) is 360 degrees.

To find the measure of the unknown angle, you can subtract the sum of the known angles from 360.

Step 1: Add the known angles together. 85.6° + 112.8° + 89.9° = 288.3°

Step 2: Subtract the sum of the known angles from 360. 360° - 288.3° = 71.7°

So, the measure of the unknown angle is 71.7°.