SOLUTION: What is the surface area of a rectangular pyramid, if the base is 6cm by 8cm and the height is 4 cm

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Question 1113945: What is the surface area of a rectangular pyramid, if the base is 6cm by 8cm and the height is 4 cm
Answer by greenestamps(13216) About Me  (Show Source):
You can put this solution on YOUR website!


The area of the base is easy -- 6%2A8=48 sq cm.

There are two triangular faces with base length 8; the altitude of each of those triangular faces is the hypotenuse of a right triangle with legs 3 and 4; that hypotenuse has length 5. So we have two triangles each with area %281%2F2%29%288%29%285%29+=+20 sq cm.

The other two triangular faces have base length 6; the altitude of each of them is the hypotenuse of a right triangle with legs 4 and 4; that hypotenuse has length 4*sqrt(2). So we have two triangles each with area %281%2F2%29%286%29%284%2Asqrt%282%29%29+=+12%2Asqrt%282%29.

The total surface area is then
48+%2B+2%2820%29+%2B+2%2812%2Asqrt%282%29%29+=+88%2B24%2Asqrt%282%29