Question

Work out the size of angle a.

angle a =
°

Give a reason why.

Work out the size of angle b.

angle b =

°

Answer 1

A = 56 degrees.

B = 34 degrees.

Explanation:

A would be the same as 56 (vertically opposite angles are equal) and B is 34 degrees because you take away a and the right angle from 180 degrees.

Answer 2

Explanation:

`\angle{a} = 56°` using the definition of vertical angles

The sum of the interior angles of a triangle is 180 so

`\angle{a} + \angle{b} + 90 = 180`

`\Rightarrow 56° + \angle{b} + 90° = 180°`

or

`\angle{b} = 34°`