Algebra help?

Question

How do I find the equation of a line going through the points (1,3) and (-2,-5)? I am lost as freakin goose and this has me stressed out.

Answer 1

1. Make sure that you copied the points correctly.

First find the slope of the line. (It is ‘m’ in the y=mx+b formula.)
To do this you will have to subtract the y values in the two points and divide them by the x values once you have subtracted them.
Now find m.

m= y2-y1/x2-x1, so m= -5-3/-2-1 It doesn’t matter which point you use first as long as you keep them straight. PS Watch out for negatives.
m=-5-3 / -2-1
m= -8 / -3
m= 8/3 The answer is positive

2. Now use the point-slope form of the line and one of the points. I am using (1,3)

y - y1 = m(x - x1)
y - 3 = 8/3(x-1) Use the distributive property.
y - 3 = 8/3x - 8/3
y = 8/3x - 8/3 + 3 Add +3 to both sides by changing 3 to 9/3 and adding it to 8/3, which = 1/3
y= 8/3x + 1/3

3. Check your answer to see if you get the same answer if you use the other point. You will.

Answer 2

first, find slope. m=(y2-y1)/(x2-x1). Then take only ONE of the two number sets, and substitue it into the same equation, and then solve for y. Example...
first find m.

m=(-5-3)/(-2-1)
solve to find m.

then, using (1,3)

(3-y)=m*(1-x)
y= -m + m*x + 3