GCSE Maths Practice: angles

Question 2 of 10

This question asks you to find a missing angle in a triangle.

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\( \begin{array}{l}\text{In a triangle, two angles measure } 60^\circ \text{ and } 50^\circ.\\ \text{What is the size of the third angle?}\end{array} \)

Choose one option:

Add known angles and subtract from 180° to find the missing angle.

In any triangle, the sum of interior angles is always 180°. To find a missing angle, add the known angles and subtract from 180°. For example, if two angles are 60° and 50°, sum = 110°. Then, 180 - 110 = 70°, so the missing angle is 70°. Understanding angle sums in triangles is essential for identifying triangle types, solving geometry problems, and applying trigonometry. This principle is also used in quadrilaterals, polygons, and real-world applications like architecture and engineering. Practicing multiple examples helps students quickly identify missing angles and reinforces geometric reasoning skills. Visualizing triangles and labeling known angles can make calculations faster and more accurate.