Question 573316
The congruent sides of an isosceles triangle measure 6cm, and the base measures 8cm. What is the area? I don't understand how you would find the necessary height of the triangle, or how the base of an isosceles triangle can be longer than the two other congruent sides. Thank you:).
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Draw the base = 8 cm
Draw the 2 sides; each = 6 cm
Draw a perpendicular bisector of the base (that is the height of the triangle).
Use Pythagoras to find the height
6^2 = 3^2 + h^2
36 = 9 + h^2
h^2 = 27
h = 3sqrt(3)
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Area = (1/2) base*height
Area = (1/2)6*3sqrt(3)
Area = 9sqrt(3) sq. cm.
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Cheers,
Stan H.
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