2d.+Regression,+equations+of+lines+using+many+data+points

1. Website: http://www.themathlab.com/Algebra/linear%20functions%20regressions%20slope/regression%20lessons/day1.htm 2. Sample Prolems:

sample 1: How can the relation between the variables in the given scatter plot be best described? (a) Weak positive correlation (b) Strong positive correlation (c) Correlation approximately 0 (d) Strong negative correlation answer: a) weak positive correlation The points are scattered in a positive but random way.

sample 2: The table below shows the age and systolic blood pressure for a group of people who recently donated blood. Draw the line of best fit for this data and estimate the equation for the line of best fit.



answer:



Pick two points on the line, and find the change in //y// over the change in //x.// Find the Y-intercept by plugging the points into the y=mx+b equation and solving for b, or in this case finding the Y-coordinate where X is zero, which is 75.

The equation then reads:

sample questions found at: http://education.yahoo.com/homework_help/math_help/problem_list?id=minialg2gt_2_1