Pearson Geometry Common Core, 2011
PG
Pearson Geometry Common Core, 2011 View details
7. Midpoint and Distance in the Coordinate Plane
Continue to next subchapter

Exercise 59 Page 56

Start with the points that are along the x- and y-axis.

A: (0,0,0)
B: (6,0,0)
C: (6, -3, 0)
D: (0,-3,0)
E: (0,0,9)
F: (6, 0, 9)
G: (0, -3, 9)

Practice makes perfect

Using the given diagram, we want to find the coordinates of the vertices of the 3D box. Coordinates in 3D are written as (x, y, z). The x- and y-axes are related in the same way they usually are. However, now we have the added dimension of moving "away from" the paper, in the z-direction. We are told that P is at (6, -3, 9).

Finding A

Notice that point A is at the origin, so the coordinate is (0,0,0).

Finding B

Point B is 6 units along the x-axis but does not move up or down in the y- or z-directions, so the coordinate is (6,0,0).

Finding D

Point D is 3 units in the negative direction on the y-axis. It does not move left or right in the x-direction and it does not move up or down in the z-direction, so the coordinate is (0,-3,0).

Finding C

Point C has the same x-coordinate as point B and the same y-coordinate as D. It also does not move up or down in the z-direction. This means that the coordinate for C is (6, -3, 0).

Finding E

Point E is 9 units up on the z-axis but does not move in the x- or y-directions, so the coordinate is (0,0,9).

Finding F

Point F has the same x-coordinate as B and the same z-coordinate as E. It does not move in either direction along the y-axis. This means that the coordinate for C is (6, 0, 9).

Finding G

Point G has the same y-coordinate as D and the same z-coordinate as E. It does not move in either direction along the x-axis. This means that the coordinate for C is (0, -3, 9).