document.write( "Question 644270: Graph the linear equation f(x)=-0.5x
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Algebra.Com's Answer #404944 by MathLover1(20849) $\"\"$ $\"About$

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To graph the linear equation you need two points on that line since any two points define a line. In the traditional Cartesian coordinate system, each of these points will be in the form ( $\"x\"$ , $\"y\"$ ) where $\"x\"$ is the position of the point on the horizontal scale and $\"y\"$ is its position on the
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\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=-0.5x\"$ \r
\n" ); document.write( "\n" ); document.write( "Pick a value for $\"x\"$ . Any value can be used, but $\"zero\"$ is often convenient. Substitute this value for $\"x\"$ in the equation and solve for $\"y\"$ .
\n" ); document.write( "In your example, the equation would become $\"f%28x%29=-0.5%2A0=0\"$ . The first point to be used to draw the line is situated at the $\"x\"$ value you chose and the $\"y\"$ value just calculated. The first point in this example would be at (0,0).\r
\n" ); document.write( "\n" ); document.write( "Pick a value for $\"y\"$ . Any value can be used, but $\"zero\"$ is often convenient. Substitute this value for $\"y\"$ in the equation and solve for $\"x\"$ .
\n" ); document.write( "In your example, the equation would become $\"0=-0.5x\"$ ..=>. $\"0%2F%28-0.5%29=x\"$ =>. $\"0=x\"$ . The second point to be used to draw the line is situated at the $\"y\"$ value you chose and the $\"x\"$ value just calculated. The second point in this example would be at (0,0).\r
\n" ); document.write( "\n" ); document.write( "Since first two points are in same spot, pick one more value for $\"x\"$ and find one more point, for example $\"x=10\"$ .
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\n" ); document.write( " $\"f%2810%29=-0.5%2A10=-5\"$
\n" ); document.write( "The third point in this example would be at ( $\"10\"$ , $\"-5\"$ ).\r
\n" ); document.write( "\n" ); document.write( "Using a straight edge, draw a line passing through both points ( $\"0\"$ , $\"0\"$ ) and ( $\"10\"$ , $\"-5\"$ ). This is the straight line defined by the linear equation.\r
\n" ); document.write( "\n" ); document.write( " $\"+graph%28+600%2C+600%2C+-10%2C+15%2C+-10%2C+15%2C+-0.5x%29+\"$ \r
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