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find the x- and y-intercept of:
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\n" ); document.write( "x-3y=-6 and
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\n" ); document.write( "x-4y=-8
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\n" ); document.write( "Think about graphing. If a point of the form (x,y) has a zero value of x, then the y
\n" ); document.write( "value has to be on the y-axis. Similarly, if a point of the form (x,y) has a zero value for
\n" ); document.write( "y then the value for x has to be on the x-axis.
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\n" ); document.write( "To demonstrate these two ideas, try plotting the point (0,6) you will see that it lies on
\n" ); document.write( "the y-axis 6 units up from the origin. This is because the x value is zero ... and that
\n" ); document.write( "requires the corresponding value of y to be on the y-axis.
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\n" ); document.write( "Next try plotting the point (3,0). You will go out 3 units on the x-axis but that is
\n" ); document.write( "where you will stay because the corresponding value of y is 0.
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\n" ); document.write( "In summary we can say that when x = 0, the corresponding value for y is on the y-axis and
\n" ); document.write( "when y = 0, the corresponding value for x is on the x-axis.
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\n" ); document.write( "Now go to the first equation which is:
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\n" ); document.write( "x - 3y = -6
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\n" ); document.write( "If we set x equal to zero we will find the corresponding value of y that is on the y-axis.
\n" ); document.write( "When x is zero in this equation, the equation is reduced to:
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\n" ); document.write( "-3y = -6
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\n" ); document.write( "Dividing both sides by -3 results in y = 2. So our point is x = 0 and y = 2 or just (0,2)
\n" ); document.write( "and this is on the y-axis which means that it is the y-intercept.
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\n" ); document.write( "If we then return to the equation, but this time we set y = 0 the equation reduces to
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\n" ); document.write( "x = -6
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\n" ); document.write( "because y is equal to 0, this point is on the x-axis as we discussed above. This point
\n" ); document.write( "is (-6,0) which means that it is the x-intercept. Now you can plot the two points
\n" ); document.write( "(0,2) and (-6,0) and these two points can be connected by a straight line running
\n" ); document.write( "through them, and this line is the graph of the equation x - 3y = -6.
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\n" ); document.write( "The same thing can be done with the second equation: x - 4y = -8
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\n" ); document.write( "First, set x = 0 and solve the equation for y. With x = 0 the equation becomes just:
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\n" ); document.write( "-4y = -8
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\n" ); document.write( "Divide both sides by -4 and you get y = 2. So the point (0,2) is on the graph. It is
\n" ); document.write( "also on the y-axis and is the y-intercept.
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\n" ); document.write( "Then set y = 0 in the equation. When you do the equation reduces to just:
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\n" ); document.write( "x = -8
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\n" ); document.write( "So the point (-8,0), which is on the x-axis is also on the graph and is the x intercept.
\n" ); document.write( "Plot the two points (0,2) and (-8,0) and extend a line through them. This is the graph
\n" ); document.write( "of this equation.
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\n" ); document.write( "Hope this helps you to understand how to get the x and y intercepts from a linear equation.
\n" ); document.write( "Just set x equal to zero to get the y intercept and next set y equal to zero to get the
\n" ); document.write( "x intercept. \n" ); document.write( "