2 problems!

12345678

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Mar 30, 2013
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1) "A pyramid has a square base of sides 20cm, and each sloping edge is 25cm long. How high is the pyramid?". Firstly I split 1 face of the pyramid in half, as it was an isosceles triangle. This gave me a right angled triangle with a base of 10cm, hyp of 25cm and I had to find the height. Using Pythagoras, I got c^2-a^2=b^2. So 25^2-10^2=525. Therefore b=22.9. However the book says the answer is 20.6cm, have I done something wrong? 2)"a corridor is3m wide and turns through a right angle". What is the longest pole that can be carried through the corridor horizontally?- really don't understand where to start on this one :s
 

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You calculated the distance from the tip of the pyramid to the center of one side, not the height.
 
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