A clear plastic prism has six faces, each of which is a parallelogram of side length 1 meter. A diagonal made of nylon filament line connecting two opposite vertices of the solid has a length of 4 meters. ls the solid a cube?

1 Answer
Dec 10, 2016

No the solid is not a cube.

Explanation:

If it were a cube, the diagonal of the base would be #sqrt2# (found using the Pythagorean theorem

#a^2 + b^2 = c^2#,

where #a# and #b# are both equal to #1# meter.

You now use a different right triangle to find the diagonal from opposite vertices, the diagonal of the base is #sqrt2#, the height is #1# (if it is a cube), and the hypotenuse is the diagonal from opposite vertices.

Again, use #a^2 + b^2 = c^2#

#1^2 + (sqrt2)^2 = 4^2#

#1 + 2 != 16#