Re: In the figure, what is the value of a ?
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09 Sep 2019, 22:12
By looking at the figure we can determine
a = 2b (vertically opposite angles) (1) and
b = 3c (vertically opposite angles) (2)
Also 6c + 3c + 2b => 9c + 2b = 180 (3)
Substitute (1) and (2) into (3), we get:
3b + a = 180 => 1.5a + a = 180
which gives, a = 180 / 2.5 = 72. Therefore, the answer is D.