How do you find the equation of a line given f(-1)=2 and f(3)=4?

Answer 1

find the line through the points (-1,2) and (3,4)

it's

y -2 = [(4-2)/(3+1)](x+1) in point slope form

y-2 (1/2)(x+1)

or

y = x/2 +5/2 in slope intercept form slope=1/2, intercept =5/2

or

-x+2y = 5 in standard form

it might help to plot the two points and draw a line through them

Answer 2

Start with two-point form

(y - 2) / (x + 1) = (4 - 2) / (3 + 1)