Describing Straight Lines Using Slope

The video tutorial explains how similar triangles can form straight lines and introduces the concept of slope as a unique number that describes a line. It discusses how ratios can be seen as single numbers and demonstrates how to calculate the slope using different triangles. The lesson emphasizes that the slope is a constant ratio of rise to run, regardless of the triangle used.

Explain why the ratio of rise to run is constant for a straight line.

How do you find the rise when given the slope of a line?