SOLUTION: find the area of an isosceles triangle if its two equal sides are20cm long and angle between them is 30 degree, without applying trigonometric method.

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Question 954671: find the area of an isosceles triangle if its two equal sides are20cm long and angle between them is 30 degree, without applying trigonometric method.
Answer by josgarithmetic(39625) About Me  (Show Source):
You can put this solution on YOUR website!
The restriction of No Trigonometry doesn't seem right. I drew a neighboring isosceles triangle to form a parallelogram to help understand the values given and findable. Tough to show here, but free-hand I could draw the picture. Used cosine and sine, and half of length equivalent to half the base.

Altitude forms two angles at top of given triangle 15 degree each.

AREA?
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