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

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�??
-----------------
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
----------------------
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)

RELATED QUESTIONS
I have no idea how to post an image, but I was able to find an exact image on another... (answered by Edwin McCravy)

Triangle ABC is an isosceles triangle. Sides AB and BC are the legs and side AC is a... (answered by vksarvepalli)

ABC is a right angle isosceles triangle, angle BCA = 90, with BC as the base and AB as... (answered by ikleyn)

Consider an isosceles triangle ABC with lengths of AB=AC=1 and angle BAC =36 degrees.... (answered by rapaljer)

ABC is an isosceles triangle with side AB= side AC. Line BC is produced to D such that... (answered by mananth,math_tutor2020)

Given an isosceles triangle ABC, where C is the vertex angle and the legs AC = BC = 10,... (answered by ikleyn,josgarithmetic)

I really need to answer these trigonometry problems. 1. The measure of two of the angles (answered by stanbon)

in a triangle ABC is anisoceles triangle [AB]=[AC] =5cm and [BC] 8cm calculate to the... (answered by Fombitz)

Triangle ABC is isosceles with AB = AC. Let D be the foot of the altitude from A on BC,... (answered by math_helper)