Find the length of the diagonal of a straight parallelepiped if A = 4m B = 3m C = 12m.

Let us find out how many meters the length of the diagonal of the rectangle will express, which lies at the base of this figure, when from the condition of the task we know that its dimensions are 4 m and 3 m:

√ (16 + 9) = √25 = 5.

Let us find out how many meters the length of the diagonal of our geometric figure will express, if from the condition of the task we know that its third dimension is equal to 12 meters:

√ (144 + 25) = √169 = 13.

Answer: With such data, the length of the diagonal of our parallelepiped will be 13 meters.