From Förberedande kurs i matematik 1

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-	{{NAVCONTENT_START}}	+	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.
-	<center> [[Bild:2_2_6a.gif]] </center>	+
-	[[Bild:2_2_6_a.gif|center]]	+	If the point of intersection has coordinates (''x'',''y''), then
-	{{NAVCONTENT_STOP}}	+
		+	{{Displayed math||
		+	<math>\left\{\begin{align} y&=3x+5\,,\\ y&=0\,\textrm{.}\qquad\quad\text{(x-axis)}\end{align}\right.</math>}}
		+
		+	If we substitute <math>y=0</math> into the first equation, we obtain
		+
		+	{{Displayed math||<math>0=3x+5,\qquad\text{i.e.}\quad x=-\frac{5}{3}\,\textrm{.}</math>}}
		+
		+	The point of intersection is (-5/3,0).
		+
		+
		+	<center>[[Image:2_2_6_a.gif|center]]</center>

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Current revision

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 (x,y), then

\displaystyle \left\{\begin{align} y&=3x+5\,,\\ y&=0\,\textrm{.}\qquad\quad\text{(x-axis)}\end{align}\right.

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

\displaystyle 0=3x+5,\qquad\text{i.e.}\quad x=-\frac{5}{3}\,\textrm{.}

The point of intersection is (-5/3,0).