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In triangle PQR,work out the values of a ,b and c.Give your reason for you answer .​

In triangle PQR,work out the values of a ,b and c.Give your reason for you answer-example-1
User Blue Bot
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1 Answer

21 votes
21 votes

Answer:

m∠a = 100°

m∠b = 100°

m∠c = 110°

Explanation:

Calculation of m∠a

∠a is an exterior angle of ΔPST .
Therefore m∠a = sum of the interior angles of ΔPST
m∠a = 30 + 70 = 100°

Calculation of m∠c

∠c and ∠PST are supplementary so their measures must add up to 180°
m∠c + 70° = 180° so m∠c = 180 - 70 = 110°

Calculation of m∠b
QRST is a quadrilateral.
The sum of the interior angles of the quadrilateral = 360°
So m∠a + m∠b + 50 + m∠c = 360°
We have already computed ∠a = 100° and ∠c = 110°
So 100 + m∠b + 50 + 110 = 360°
260 + m∠b = 360
m∠b = 360 - 260 = 100°



User Michael Parker
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