SOLUTION: the ratio of the measures of three sides of a triangle are 5:7:8 find the angle measures help pls

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Question 942370: the ratio of the measures of three sides of a triangle are 5:7:8 find the angle measures help pls
Found 2 solutions by Alan3354, MathLover1:
Answer by Alan3354(69443) About Me  (Show Source):
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the ratio of the measures of three sides of a triangle are 5:7:8 find the angle measures
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Find the 3 angles.
Use the Cosine Law to find the 1st angle.
Use sides of 5, 7 & 8.
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a = 5
b = 7
c = 8
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5/sin(A) = 7/sin(B) = 8/sin(C)
The ratio of the angles is not the ratio of the sides.

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

the ratio of the measures of three sides of a triangle are 5%3A7%3A8 find the angle measures
5x%2B7x%2B8x=180
20x=180
x=180%2F20
x=9 thuis is the multiplier for all angles thus
5%2A9=45 the measure of the first angle
7%2A9=63 the measure of the second angle
8%2A9=72 the measure of the third angle
check:
45%2B63%2B72=180
180=180+