THE EQUATION OF A LINE DANCE
The equation of a line dance is a kinesthetic activity from which the method of finding the slope and intercept of a line can derived. The basic dance step is done to the beat [1,2,rest]. Before beginning the step, this beat may be snapped, clapped or tapped. For example: [snap,snap,clap] or [clap,clap,tap]. When the students are comfortable with the rhythm, the basic step can be taught.
In the diagram,
the pairs of feet show where the step sequence begins, and the orientation of
the numbers show whether you step forward or backward. In the top diagram the
dancers feet start together on the x and 0, the 0-foot steps forward to 1, then
the x-foot takes a half-step forward to the next 0, beside the 1. The pattern is
repeated always starting with the 0-foot to complete the previous half-step. The
step and beat together are
Once the basic step is learned students are ready to learn the dance. In diagram A, the blue and the diagram, show how partners line up to begin the dance. The blue partner repeats the basic step a (x1) number of times forward, makes a ninety-degree turn to the right and repeats the basic step a (y1) number of times backward. The blue partner continues in diagram B; repeating the basic step a (y2) number of times forward, makes a ninety-degree turn to the left and repeats the basic step a (x2) number of times backward.
After the blue partners dance
sequence, the dancers will be arranged as shown in diagram C. The change is
equal the slope of the line on which (x,y) points would lie. Now the green
partner does a promenade down the slope, using the basic step, until they
approximately intersect the y-axis, diagram D. Last the blue partner follows the
green and lines up behind them. The dance is repeated with the green dancer
going first. Eventually a group of partners should all dance together.
The purpose of the dance is to create a picture of how to find the slope and intercept, not to actually find these so the dance does not have to render these exactly. Students can have a lot of fun with this dance and will be excited by the connection to their math work.