Q3 of 45 Page 27

The measures of angles of a triangle are x°, (x – 20)°, (x – 40)°. Find the measure of each angle.

Angles of a triangle are


In a triangle we know sum of interior angles is 180°


∴ x° + (x – 20)° + (x – 40)° = 180°


x° + x° - 20° + x° - 40° = 180°


3x° = 180° + 60°


x° = 240°/3


∴ x° = 80°


Angles of the triangle are x° = 80°


(x – 20)° = 80° - 20° = 60°


(x – 40)° = 80° - 40° = 40°


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