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You can do this problem without an equation if you would like. All you need is an understanding
\n" ); document.write( "of the concept of slope. The slope of a line can be interpreted as \"If you go one unit horizontally
\n" ); document.write( "to the right from a point on the line, from that new point ... how many units do you go vertically
\n" ); document.write( "up or down to get back to the line.
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\n" ); document.write( "In this problem you are told that one point on the line (the y-intercept) is (0, 4). That
\n" ); document.write( "point is on the y-axis at +4. Then you are told that the slope is -2. The minus sign tells
\n" ); document.write( "you that the slope is down as you go to the right. So you can start at the intercept
\n" ); document.write( "on the y-axis (because you know (0, 4) is on the graph. From that point go one unit
\n" ); document.write( "horizontally to the right and from there go down 2 units. Stop there and mark that point
\n" ); document.write( "because it is on the graph. Then starting from the new point you marked, you can again move
\n" ); document.write( "one unit horizontally to the right and from there go down 2 units and mark that as another
\n" ); document.write( "point on the graph. And once you get the hang of this process, you can do it in multiples.
\n" ); document.write( "For example, in this problem you could start at the y-intercept, and from there move 5 units
\n" ); document.write( "horizontally (this would put you at the point (5, 4) ) and then move down 10 units
\n" ); document.write( "(from 5 times the slope which is 5*-2). You should be at the point (5, -6) where the -6
\n" ); document.write( "comes from 4 - 10.
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\n" ); document.write( "When you get done, your graph should look like this:
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\n" ); document.write( "Hope this method doesn't confuse you too much. It may help you to understand the concept of
\n" ); document.write( "slope and how it relates to graphing.
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\n" ); document.write( "If this method is not clear, you could always use the slope intercept form of an equation
\n" ); document.write( "to calculate other points on the graph. The slope intercept form is:
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\n" ); document.write( "y = mx + b
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\n" ); document.write( "where m is the slope and b is the value of y where the graph crosses the y axis. In this
\n" ); document.write( "problem you were given that the slope (m) is -2 and that the graph crosses the y axis at +4.
\n" ); document.write( "Substituting these values into the equation converts it to:
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\n" ); document.write( "y = -2x + 4
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\n" ); document.write( "You can now use this equation to find other points on the graph. For example, previously
\n" ); document.write( "we found that the point (5, -6) is on the graph. So if we assume that x is 5 and plug that
\n" ); document.write( "value into the equation we get:
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\n" ); document.write( "y = -2*5 + 4 = -10 + 4 = -6
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\n" ); document.write( "This tells us that when x = 5 then y = -6 so the point (5, -6) is on the graph.
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\n" ); document.write( "You can find other points on the graph by letting x be other values of your choice and
\n" ); document.write( "using the equation to compute the value of y that corresponds to each value of x. Then
\n" ); document.write( "plot the points you get. \n" ); document.write( "