Question

What is the equation in point slope form of the line that passes through the points (-1, 4) and (3,-4) ?

A. y-3=-2(x+4)

B.y-4=2(x+3)

C.y+4=-2(x-3)

D.y+4=2(x-3)

Answer 1

The point-slope form:

`y-y_1=m(x-x_1)`

The formula of a slope:

`m=(y_2-y_1)/(x_2-x_1)`

We have the points (-1, 4) and (3, -4). Substitute:

`m=d(-4-4)/(3-(-1))=(-8)/(4)=-2\\\\y-(-4)=-2(x-3)\\\\\boxed{y+4=-2(x-3)}\to\boxed{C.}`