Answer:
- SA = 18.2 +12.2h
- SA = 67 yd²
Step-by-step explanation:
The surface area of a rectangular prism is the sum of the areas of the six rectangular faces. Of course, opposite faces have the same area, so the formula can be written ...
SA = 2(LW +LH +WH) = 2(LW +H(L +W))
For your given values, this can be simplified to ...
SA = 2(2.6·3.5 +h(2.6 +3.5)) = 2(9.1 +6.1h)
SA = 18.2 +12.2h
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For h=4, the surface area is ...
SA = 18.2 +12.2·4 = 18.2 +48.8
SA = 67 . . . yd²
