Answer:
1.79 m²
Step-by-step explanation:
the other answer is correct.
that approach works, because it is a regular prism with equal heights and equal depths along the whole object.
in general you need to add all individual surface areas.
in our case here we have 5 of them :
top and bottom rectangles
front and back side triangles
left side rectangle
so, the top rectangle is
1×0.81 = 0.81 m²
the bottom rectangle is
1×0.8 = 0.8 m²
a single triangle is
0.1×0.8/2 = 0.04 m²
so, front and back triangles are
2×0.04 = 0.08 m²
the left side rectangle is
0.1×1 = 0.1 m²
so, the whole surface area is
0.81 + 0.8 + 0.08 + 0.1 = 1.79 m²
of course, it is the same result (as I said, the other answer is correct too), but this shows the more general approach for other, more general prisms.
