SOLUTION: an isosceles triangle has sides of length 8cm, 8cm and 5cm find the angle between the two equal sides. how do you figure out the angle using trigonometry?

Algebra ->  Triangles -> SOLUTION: an isosceles triangle has sides of length 8cm, 8cm and 5cm find the angle between the two equal sides. how do you figure out the angle using trigonometry?       Log On


   

Question 793768: an isosceles triangle has sides of length 8cm, 8cm and 5cm find the angle between the two equal sides. how do you figure out the angle using trigonometry?
Answer by josgarithmetic(39615) About Me  (Show Source):
You can put this solution on YOUR website!
Vertex of the equal sides has an altitude extending from it to the middle of the third side, intersecting this third side in the middle, forming two right triangles. Each such triangle has hypotenuse 8 cm and short leg 2.5 cm.

sine%28atVertex%29=2.5%2F8 for each right triangle, but for the entire isosceles triangle, sin%282%2AatVertex%29=2.5%2F8, so wanted is 2%2Aarcsin%282.5%2F8%29.