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A pyramid has a square base which has an area of 1440 . Each of the pyramid’s triangular faces is identical and each has an area of 840.  Find the height of the pyramid.     

 

sqrt(1440)  =  37.95      This is the side of the square base.     

 

Area_triangle  =  (1/2) • base • height     

            840  =  (1/2) • 37.95 • h     

                h  =  840 / 18.98     

                h  =  44.27     This is the slant height.     

 

       c²  =  a² + b²     

44.27²  =  18.98² + b²     

   1960  =  360 + b²     

        b²  =  1600     

        b¹  =  40                This is the height from the center of the base to the apex.     

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