Answer:
Q16a: 432 cm³
Q16b: sides: 20 m, 6 m; height: 13 m.
Explanation:
Q16a
Each cube will have a volume ...
V = s³
V = (6 cm)³ = 216 cm³
The two cubes together will have a volume that is twice that.
The cuboid volume is 432 cm³.
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Q16b
Let h represent the height of the trapezium. Then its area is ...
A = 1/2(b1 +b2)h
169 = 1/2((h +7) +(h -7))h = 1/2(2h²) = h²
h = √169 = 13 . . . . . distance between the parallel sides
The side lengths are h+7 = 20 m and h-7 = 6 m. The distance between them is 13 m.