The diagram shows three straight lines work out the size of angles a, b and c.
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Answer:
a = 21°
b = 70°
c = 89°
Step-by-step explanation:
a = 21° as vertically opposite angles are equal
to work out b:
angles on a straight line add up to 180
b + 110 = 180
b = 180 - 110
b = 70°
to work out c:
the sum of angles in a triangle add up to 180
we have a and b
21 + 70 + c = 180
91 + c = 180
c = 180 - 91
c = 89°