The form of linear equation that describes line is:
[tex]y=sx+n[/tex]
First we must calculate the slope.
[tex]s=\dfrac{\Delta{y}}{\Delta{x}}=\dfrac{2-(-3)}{4-2}=\dfrac{5}{2}[/tex]
Now it looks a bit more like this:
[tex]y=\dfrac{5}{2}x+n[/tex]
All we need now is to put in y and x from one point doesn't matter which. I'll pick A.
The equation now looks like this:
[tex]-3=\dfrac{5}{2}\cdot2+n[/tex]
Solve for n.
[tex]
-3=5+n \\
n=-8
[/tex]
And finally write the equation.
[tex]f(x)=\dfrac{5}{2}x-8[/tex]
Hope this helps.
r3t40