Answer:
Height is 5.5 cm²
Step-by-step explanation:
We already know the area of the bases. Subtract the area of the bases from the surface area.
100 x 2 = 200 (there are two bases)
420 - 200 = 220
That leaves us with 4 sides. Divide 220 by 4 to find the surface area of one side.
220 ÷ 4 = 55
We already know the length of the side is 10, so divide 55 by 10 to find the height.
55 ÷ 10 = 5.5
