9514 1404 393
Answer:
see attached
Explanation:
The total surface area is the sum of the areas of the triangular faces and the rectangular base. The base area is given by the formula ...
A = LW . . . . . the product of length and width
The triangle area is given by ...
A = 1/2bh . . . . where b is the base width (same as the rectangular base dimension) and h is the slant height.
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The total area is the sum of the areas of the two sets of congruent triangles on opposite faces and the base area.
For the number of problems you have, it is much less tedious to simply enter the formulas in a spreadsheet and let it do the calculations.
In the attached, we have columns for the base dimensions, the corresponding slant heights, the triangle areas, the base area, and the total surface area of the pyramid. The area you seek is in the rightmost column. (Pay attention to problem number.)
The units in each case are the square of the units of the linear dimensions. In problem number order, they are {in², m², ft², km², yd², m²}.