### Home > A2C > Chapter 7 > Lesson 7.1.2 > Problem 7-21

7-21.

For each of the following equations, find every point where its *three-dimensional* graph intersects one of the coordinate axes. That is, find the *x*-, *y*- and *z-*intercepts. Express your answer in (*x*, *y*, *z*) form. .

To find the intercept of a given axis, set all other variables to zero.

For example, the *y*-intercept will be

To find the *y*-intercept, let and

Repeat the process to find the *z*-intercept.

See part (a):

See part (a).

Note: You will have two *x*-intercepts and two *z*-intercepts. Why

See part (a):

Use the eTool below to test your solutions to parts (a), (b) and (c) above.

Click the link at right for the full version of the eTool: *7-21 HW eTool*