What is the x-intercept of the line that contains the points (-4, 1) and (-7, 2) in the standard (x, y) coordinate plane?

1 Answer
Apr 17, 2017

(see below)

Explanation:

Find the equation of the line:

  1. Find the gradient using dy/dx
    (1-2)/(-4+7) = -1/3

  2. Take 1 coordinate point and use y-y_1 = m (x-x_1) to find the equation of the line
    y-1 = -1/3 ( x - (-4) )
    y-1 = -1/3x - 4/3
    y = -1/3x - 1/3

  3. substitute 0 into y to find the x-intercept.

y= -1/3x