Re: Considering each choice separately, having values for
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24 Sep 2017, 07:13
Let's analyze the answers one by one:
a) b°: b alone is not enough to compute a unless we know c
b) c°: same reason as above, we need b too
c) d°: d is enough because lines m and n are parallel and thus d is equal to the supplementary angle of a so that a can be found as 180-d°
d) b° and c°: as we anticipate above, b and c together are enough to compute a since a is supplementary to the third angle of the triangle with b and c that can be found as 180°-b°-c°
e) c° and e°: they are enough too because e is supplementary to b so it is as we have b and c so as above they are enough
f) b° and f°: thanks to parallelism, f is supplementary to angle c so we are still in the b and c case so that they are enough to compute a
g) c° and f°: they are not enough since f is not of help in computing b.
To sum up the answers are C,D,E,F