Linear functions

The chart below shows the graph of the function $y=a\,x+b$. Functions of this form are called linear functions. When you access this site the parameters $a$ and $b$ are set to the values $a=2$ and $b=1$. So you see at the beginning the the graph of $y=2\,x+1$.

Change yourself using sliders the values of $a$ and $b$.You see that the parameter $a$ acts on the slope of the line, which is the graph of this.
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