What is the difference between length and distance?

Length is the measurement of something, such as a segment or the dimensions of a room.

Distance is how far apart objects are, such as two cities or two points. Neither length nor distance will ever be a negative value.

Use this Distance Applet to create the segment lengths shown in the table below. Click on the blanks to reveal some possible endpoints for A and B. Your coordinates will vary.

Answer the following questions. Click on the blanks to check your answers.

Look at data for the horizontal segments you created. Were the y-coordinate values the same in both points?Interactive button. Assistance may be required. _____ yes

Remember that length and distance must both be a positive value, so if we take the absolute value of the difference we’ll get a positive value every time.

|x₁ − x_x| = positive

Look at the data for the vertical segments you created.Were the x-coordinate values the same in both points?Interactive button. Assistance may be required. _____ yes

So, it turns out that when lines are horizontal or vertical we don’t use all the information to find the distance. Or do we?

Think about the segment you created with a slope of 3 over 4 3 4 ; was it easy to see the distance of this line by looking at the graph?Interactive button. Assistance may be required. _____ no

If the lines are not horizontal or vertical and the endpoints are known, the Distance Formula is used to find the distance between the two points or the length of the segment.