Question

Write an equation (in slope-intercept form) for the line that passes through the points (4, 8) and (6, 2).

Answer 1

Explanation:

Slope-intercept form implies that we need the slope...so let's do that first. The formula to find the slope being given 2 coordinates is

`m=(y_2-y_1)/(x_2-x_1)` so filling in:

`m=(2-8)/(6-4)=(-6)/(2)=-3` so the slope is -3. Now we will use that slope in the point-slope form of a line and write the equation.

Point-slope form is

`y-y_1=m(x-x_1)` and filling in:

y - 8 = 3(x - 4) (you can choose either point to use for x and y; you'll get the same equation either way...PROMISE!)

y - 8 = 3x - 12 and

y = 3x - 12 + 8 so

y = 3x - 4 and that's the line in slope-intercept form.