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Work out the size of angle a and angle b

Work out the size of angle a and angle b-example-1
User Luke Baughan
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1 Answer

21 votes
21 votes

Answer:

a = 120°

b = 60°

Explanation:

Angle a and 60° are suplementary. The sum of supplementary angles is 180° (straight angle).

a + 60° = 180°

a = 180° - 60°

a = 120°

The sum of angles in the quadrilateral is 360°. Notice how two of the angles in the quadrilateral are marked as right angles (angles marked with a square). Each of them is 90°.

b + 90° + a + 90° = 360°

Substitute a with the value calculated in the previous step.

b + 90° + 120° + 90° = 360°

Solve for b.

b + 300° = 360°

b = 60°

Work out the size of angle a and angle b-example-1
User Ankur Banerjee
by
2.6k points