Question

In the figure above, vertex G of the rectangular solid shown has coordinates (5, 6, 4). What is the length of the diagonal CF?
(A) 11.81
(B) 8.77
(C) 7.81
(D) 7.21
(E) 6.40

Answer 1

To find the length of diagonal CF, we can use the distance formula in three dimensions.
The coordinates of point C are (0, 0, 0) and the coordinates of point F are (5, 6, 4).
Thus the length of diagonal CF = sqrt((5-0)^2 + (6-0)^2 + (4-0)^2)
= sqrt(25 + 36 + 16)
= sqrt(77)
= 8.77
Therefore, the length of the diagonal CF is 8.77, which is answer choice (B).