## Tuesday, November 9, 2010

### Ch 1 Project - Modeling with Functions and Regression Equations

1. The first thing i did was draw the shapes and their diagonals. The triangle is excluded because it doesn't have any diagonals.
2. Next, I made a scatter plot of the data. The values of n (number of sides) went in the L1 column and the values of d (number of diagonals) went in the L2 column.
3. Next, I used the calculator to find the linear regression, power regression, quadratic regression, cubic, and quartic regression. The closer the absolute value or r or R^2 is closer to 1, then the closer it is fitting the data.
4.After all that, i found that the quadratic regression perfectly fitted the data. The equation is 0.5x^2 - 1.5x. R^2 is a positive 1, so it tells me that the correlation is positive and that the curve fits the data perfectly.
5.Finally, i used my equation 0.5x^2 - 1.5x. to find the number of diagonals in a 150-gon. I plugged in 150 for x and got 11,025. Therefore, the number of diagonals in a 150-gon is 11,025