Answer:
544 units²
Step-by-step explanation:
The surface area is the sum of the areas of the three rectangular faces and the two triangular bases.
SA = 10×14 +10×14 +12×14 + 2(1/2)(12)(8)
= 14×(10+10+12) +12×8
= 448 +96
= 544 . . . . square units
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The area of a rectangle is the product of its dimensions:
A = LW
The area of a triangle is half the product of its base and height:
A = (1/2)bh
Here, both triangles have the same area, so we multiplied the area of one of them by 2 to get the area of both of them.