The angular measure L is : 47°
<h3>What are angles?</h3>
Angles are formed when two lines meet.
Analysis:
Firstly, we calculate for m using cosine rule.
= + -2(510)(820) cos 20
= 260100 + 672400 -83600(0.9396)
= 146618.56
m = = 382.9cm
using sine rule to find ∠L
382.9/sin20 = 820/sinL
sinL = 820sin20/382.9
sinL = 820(0.342)/382.9
sinL = 0.732
L = sin inverse of 0.732 = 47°
In conclusion, ∠L is 47°
Learn more about sine and cosine rule: brainly.com/question/4372174
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