Solution 2.2:6a

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According to the definition, the point of intersection between two lines is that point which lies on both lines; it must therefore satisfy the equations of both lines.
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If the point of intersection has coordinates
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<math>\left( x \right.,\left. y \right)</math>, then
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<math>y=3x+5</math>
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and
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<math>y=0</math>
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(
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<math>x</math>
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-axis)
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If we substitute
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<math>y=0</math>
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into the first equation, we obtain
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<math>0=3x+5</math>
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i.e.
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<math>x=-\frac{5}{3}</math>
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The point of intersection is
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<math>\left( -\frac{5}{3} \right.,\left. 0 \right)</math>.
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<center> [[Image:2_2_6a.gif]] </center>
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[[Image:2_2_6_a.gif|center]]
[[Image:2_2_6_a.gif|center]]
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Revision as of 10:16, 18 September 2008

According to the definition, the point of intersection between two lines is that point which lies on both lines; it must therefore satisfy the equations of both lines.

If the point of intersection has coordinates \displaystyle \left( x \right.,\left. y \right), then

\displaystyle y=3x+5

and

\displaystyle y=0 ( \displaystyle x -axis)

If we substitute \displaystyle y=0 into the first equation, we obtain


\displaystyle 0=3x+5 i.e. \displaystyle x=-\frac{5}{3}


The point of intersection is \displaystyle \left( -\frac{5}{3} \right.,\left. 0 \right).