Why must angle A be 135°
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Answer:
Because a is the measure of the interior angle of a regular octagon.
Step-by-step explanation:
Given figure is of a regular octagon.
Measure of one interior angle of regular octagon is given as:
[tex]a = \frac{(n - 2) \times 180 \degree}{n} \\ \\ = \frac{(8 - 2) \times 180 \degree}{8} \\ \\ = \frac{6 \times180 \degree }{8} \\ \\ = \frac{1080 \degree}{8} \\ \\ \huge \red{ \boxed{a= 135 \degree}}[/tex]