# Linear Law

• Nov 28th 2012, 12:56 PM
peugeotgtidanny
Linear Law
I have plotted a Linear graph, using P1 and P2. I now need to determin by calculation the "Law of the line".
P1 (-2, -6.2) and P2 ( 3, 4.8)

Can anyone help?
• Nov 28th 2012, 12:58 PM
Plato
Re: Linear Law
Quote:

Originally Posted by peugeotgtidanny
I have plotted a Linear graph, using P1 and P2. I now need to determin by calculation the "Law of the line".
P1 (-2, -6.2) and P2 ( 3, 4.8) Can anyone help?

Can you tell what the heck Law of the line could possibly be?
• Nov 28th 2012, 01:16 PM
peugeotgtidanny
Re: Linear Law
I think its:
Gradient = y divided by x
• Nov 28th 2012, 01:28 PM
Plato
Re: Linear Law
Quote:

Originally Posted by peugeotgtidanny
I think its:
Gradient = y divided by x

Given the points $(x_1,y_1)~\&~(x_2,y_2)$ the line determined is

$(y-y_1)=\left(\frac{y_2-y_1}{x_2-x_1}\right)(x-x_1)$ if $x_2-x_1\ne 0$
• Nov 29th 2012, 04:34 PM
HallsofIvy
Re: Linear Law
That is normally referred to as the "slope" of the line.