I am having trouble finding the length of a sloping edge in the following problem:

A right pyramid, ht 6 cm stands on a square base of side 5cm. Find the legth of a sloping edge and the area of a triangular face.

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- May 12th 2013, 09:34 PMelmidgeTrigonometry - modelling and problem solving
I am having trouble finding the length of a sloping edge in the following problem:

A right pyramid, ht 6 cm stands on a square base of side 5cm. Find the legth of a sloping edge and the area of a triangular face. - May 17th 2013, 11:04 AMx3bnmRe: Trigonometry - modelling and problem solving
Suppose the right pyramid is like the one in the following image:

Attachment 28398

Right pyramid has a square base . This square base has all equal sides where each side has length . We also know that the height of the right pyramid is which is

Now in sqare , is a right triangle with a right angle.

So by Pythogorean theorem:

But

So

We know that

Now is a right triangle with a right angle.

So:

That's the length of the slopping edge which is

So the area of:

So the area of the triangular face is