How do you write an equation in point slope form given (–2, 0) and (2, 8)?

1 Answer
Mar 26, 2017

See the entire solution process below:

Explanation:

First, we need to determine the slope of the line which goes through the two points given in the problem. The slope can be found by using the formula: #m = (color(red)(y_2) - color(blue)(y_1))/(color(red)(x_2) - color(blue)(x_1))#

Where #m# is the slope and (#color(blue)(x_1, y_1)#) and (#color(red)(x_2, y_2)#) are the two points on the line.

Substituting the values from the points in the problem gives:

#m = (color(red)(8) - color(blue)(0))/(color(red)(2) - color(blue)(-2))= (color(red)(8) - color(blue)(0))/(color(red)(2) + color(blue)(2)) = 8/4 = 2#

The point-slope formula states: #(y - color(red)(y_1)) = color(blue)(m)(x - color(red)(x_1))#

Where #color(blue)(m)# is the slope and #color(red)(((x_1, y_1)))# is a point the line passes through.

Substituting the slope we calculated and the first point from the problem gives:

#(y - color(red)(0)) = color(blue)(2)(x - color(red)(-2))#

#(y - color(red)(0)) = color(blue)(2)(x + color(red)(2))#

We can also substitute the slope we calculated and the second point from the problem giving:

#(y - color(red)(8)) = color(blue)(2)(x - color(red)(2))#