What is the equation of the line passing through (8,2), (5,8)?

1 Answer
Jan 4, 2016

In general form:

2x+y-18 = 0

Explanation:

The slope m of a line passing through two points (x_1, y_1) and (x_2, y_2) is given by the equation:

m = (Delta y)/(Delta x) = (y_2-y_1)/(x_2-x_1)

Let (x_1, y_1) = (8, 2) and (x_2, y_2) = (5, 8)

Then:

m = (8-2)/(5-8) = 6/(-3) = -2

The equation of the line passing through (8, 2) and (5, 8) can be written in point slope form as:

y - y_1 = m(x-x_1)

That is:

y - 2 = -2(x - 8)

Add 2 to both sides to find:

y = -2x+18

which is the slope intercept form of the equation of the line.

Then putting all terms on one side by adding 2x-18 to both sides we find:

2x+y-18 = 0

which is the general form of the equation of a line.