You can
put this solution on YOUR website!Graph the lines. If you need help with this, then see my recently posted Lesson Plan called Graphing and Slope of a Line.
Remember that you have TWO separate lines to graph. Each of those lines has a y-intercept, which is the point on the y-axis where the graph crosses and also it is the point where x=0. That's the first point to graph.
Locate the y-intercept for the first line, which is y=-x+3, where the y intercept is 3. So go up three units on the y axis, and put the first point. Next, the slope of the line is the coefficient of x, which is -1. This slope of -1 can be written as
, which means that you have a rise of -1 (like DOWN 1), and over (to the RIGHT) 1 unit. Start with your pencil on the y intercept, and from that point, move DOWN 1, and right 1, and put another point. Then connect the points, and you have the first line.
For the second line y = x-4, the yintercept is -4, and the slope is 1 which means that m= 1/1. Start with the y intercept by going DOWN 4 on the y axis and put a point. With your pencil on this point, and move UP 1 and to the RIGHT 1 unit, and put another point. Connect these points and you will get the line.
See if these graphs agree with this:
From looking at the graph, it looks like the two graphs intersect at about halfway between 3 and 4. Let's take a guess at x = 3.5. Y is between -1 and 0. Guess that y is about -.5. The solution rounded to the nearest half would be (3.5, -.5).
R^2 at SCC
