SOLUTION: How do I calculate side BC of an Isosceles triangle when the two equal sides AB and AC are 12 and angle A [BAC] is 130°??
Thank you for any help
Jasmine
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-> SOLUTION: How do I calculate side BC of an Isosceles triangle when the two equal sides AB and AC are 12 and angle A [BAC] is 130°??
Thank you for any help
Jasmine
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Question 247756: How do I calculate side BC of an Isosceles triangle when the two equal sides AB and AC are 12 and angle A [BAC] is 130°??
Thank you for any help
Jasmine Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! How do I calculate side BC of an Isosceles triangle when the two equal sides AB and AC are 12 and angle A [BAC] is 130°??
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You can use the Law of Sines:
a/sin(A) = b/sin(B)
Angles B and C are 25 degs (since it's an isosceles)
a = 12*sin(130)/sin(25)
a =~ 21.75
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You can also drop an altitude from A. Then a/2 = 12*sin(65)
a = 24*sin(65)
a =~ 21.75 (again, it's monotonous)
