Lines in Coordinate Systems

Drawing and reading off a linear function

This video explains in detail how to draw a staight line and how to read a line equation from the coordinate system.

Line through two given points

Connect the two points. If a function equation $g(x)=mx+tg(x)\backslash ;=\backslash ;mx+t$ is given, then you can always calculate two points by inserting two different $xx$- values and then draw the straight line through both points.

Straight line from line equation

1. Draw the $yy$-axis intercept as a point.

2. If the slope is given as a decimal number, go 1 to the right and the value of the slope up.

   If the slope is given as a common fraction, go the value of the denominator to the right and the value of the numerator up.

3. Connect the two points to form a straight line.

Beispiel: $g(x)=2x+1g(x)\backslash ;=\backslash ;2x+1$

Plotting lines

Reading off line equations a coordinate system

Way 1:

If the straight line is given as a graph in a coordinate system, you can read off any two points from the coordinate system through which the straight line passes. With these two points you can obtain the general line equation.

Way 2:

If the line intersects the $yy$-axis at a point with integer coordinates, the $yy$-axis intercept can be read directly and the slope determined from another suitable point.

If the line does not do this, the first way is recommended.