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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-> 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) (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.