how do you decide if the angles in a parallelopiped are 90 degrees?

Question

directrix · Answer

If the parallelepiped is a rectangular solid, then it has right angles. 
The questions seems vague. Is there more to the question other than what you posted? 
@NyikoPearl

anonymous · Answer

If all the angles are 90, then it will be a box.

anonymous · Answer

the points A(1,3,2) B(3,-2,2) C(2,1,3) and D(1,-1,0) are given and the question are :
a) does the base lie on a horzontal plane?
b) decide if any angles in the parallelopiped are 90 degress
c) find the co ordinates of the other four points
please help this chapter is new to me and im struggling

anonymous · Answer

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anonymous · Answer

Is this vector calculus?

anonymous · Answer

yes Wio

anonymous · Answer

Okay, take every point and subtract point A from it.

anonymous · Answer

That will give you 3 vectors for the parallelopiped.

anonymous · Answer

Find those vectors first.

anonymous · Answer

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