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The diagram shows three straight lines work out the size of angles a, b and c.

The diagram shows three straight lines work out the size of angles a, b and c.-example-1
User Jottr
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1 Answer

10 votes

Answer:

a = 21°

b = 70°

c = 89°

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°

User Hedinn
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