Question

yu - xi draws a triangle with two angles measuring 79° and 23°. what is the measure, in degrees, of the third angle?

Explanation:

Step1: Recall the sum of angles in a triangle

The sum of the interior angles of a triangle is \(180^{\circ}\). Let the three angles of the triangle be \(A = 79^{\circ}\), \(B=23^{\circ}\), and \(C\) (the unknown angle). Then \(A + B + C=180^{\circ}\).

Step2: Solve for the unknown angle

We can rewrite the formula from Step 1 as \(C = 180^{\circ}-(A + B)\). Substitute \(A = 79^{\circ}\) and \(B = 23^{\circ}\) into the formula: \(C=180-(79 + 23)\). First, calculate \(79+23 = 102\). Then \(C=180 - 102\).

Step3: Calculate the value

\(180-102 = 78\).

Answer:

78