Answer:
The measure of the unknown angle is 30°.
Explanation:
Let the measure of the unknown angle be x°.
Supplementary angles are two angles whose measures sum to 180°.
Complementary angles are two angles whose measures sum to 90°.
Therefore, the supplement of x° is (180 - x)°, and its complement is (90 - x)°.
Given that the supplement is 30° more than twice its complement:
(180 - x)° = 2(90 - x)° + 30°
To find the measure of the angle, solve the equation:
⇒ (180 - x)° = (180 - 2x)° + 30°
⇒ 180° - x° = 180° - 2x° + 30°
⇒ 180° - x° = 210° - 2x°
⇒ 180° - x° + 2x° = 210° - 2x° + 2x°
⇒ 180° + x° = 210°
⇒ 180° + x° - 180° = 210° - 180°
⇒ x° = 30°
Therefore, the measure of the unknown angle is 30°.