Question

Find the equation of the line (1, -2) and (5, -4) in the form y=mx +b

Answer 1

\[y=-\frac{ 1 }{ 2 }x -\frac{ 3 }{ 2 }\]

Answer 2

you use this formula
(y2-y1)/(x2-x1)

and you have 2 points...which is all you need
(-4 + 2)/(5-1)
-2/4
simplified is -1/2

this is your slope

now apply this to your point slope formula

y - y1 = m(x - x1)
m is your slope
pick one of the 2 points you have...and put the y where you see y1...and put the x where you see x1

so

y - (-2) = -1/2(x - 1)
y + 2 = -1/2x + 1/2
subtract 2 from both sides

y = -1/2x + (1/2 - 2)
find lcd of 1/2 and 2

which means 1/2 - 4/2
which becomes -3/2

so now you have

y = -1/2x - 3/2