# Coordinate Geometry: Quick Investigation

- Author:
- Tim Brzezinski

- Topic:
- Constructions, Geometry, Straight Lines

**Directions:**1) Graph any line. 2) Plot a point anywhere NOT ON THAT LINE. 3) Construct a line PARALLEL to the GIVEN LINE. Go to the questions below the applet. Please answer these.

## 4.

Use the slope tool to measure and display the slopes of both lines. What do you immediately notice?

## 5.

Select the **Move** arrow now. Drag any one or more of the orange points of the first line around. Does the phenomenon you described in your response to (4) above still hold true?

## 6.

In general, what can we conclude about any two non-vertical lines drawn in the coordinate plane?