Standard form of line through (-2, 3) and (4, 12)

[lovenatasha]

I need to know how to find and equation of a line in standard form when given 2 points on the line, such as: (-2, 3) and (4, 12). Any help would be appreciated. Thanks.

 

[pka]

There are two basic standard forms of a line: Ax+By=C or Ax+By+C=0.
I do not know which one your text material uses.
In either case if the slope, m, is defined then (-A/B)=m and find C by substituting one of the points.
For example given (-2,5) & (2,10) the slope (change in y)/(change in x) is 5/4.
So A=-5 and B=4 or –5x+4y=C.
Use (-2,5) to find C: C=(-5)(-2)+(4)(5)=30 or –5x+4y=30.
We would probably not ‘lead’ with a minus, so write it as 5x-4y=-30.

 

[lovenatasha]

Ok

Thanks, I believe I was actually on the right track. So the anwser to the problem with (-2,3) and (4,12) would be 3x+2y=0 correct?

 

[pka]

Not quite!
The slope is 3/2.
Try again.