SOLUTION: find the height of a isosceles triangle whose base is 10cm and legs are 20 cm (leave your answer in simplest radical form)

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Question 549918: find the height of a isosceles triangle whose base is 10cm and legs are 20 cm (leave your answer in simplest radical form)
Answer by KMST(5328) About Me  (Show Source):
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The height is h, the length of the altitude through the vertex. It is a median and part of the perpendicular bisector of the base. It divides the isosceles triangle into two symmetrical, congruent right triangles.
With all lengths in cm, Pythagoras' theorem says that
h%5E2%2B5%5E2=20%5E2 --> h%5E2%2B25=400 --> h%5E2=400-25=375 --> h=sqrt%28375%29=sqrt%2825%2A15%29=sqrt%2825%29%2Asqrt%2815%29=5sqrt%2815%29
That's an irrational number, and its exact value cannot be expressed in decimal form.
It's approximately 19.365, or 19.36, or 19.4 (depending on how precise you want to be).