How do you write the equation in point slope form given (2, 5) (3,10)?

2 Answers
Jun 2, 2016

y-5=5(x-2)

Explanation:

In general, given two points (x_1,y_1) and (x_2,y_2)
the slope can be calculated as
color(white)("XXX")m=(y_2-y_1)/(x_2-x_1)

and the equation of the line through these points using the point slope form is
color(white)("XXX")(y-y_1)=m(x-x_1)color(white)("XXXXX")see below for other forms

Given
color(white)("XXX")(x_1,y_1)=(2,5) and
color(white)("XXX")(x_2,y_2)=(3,10)

m=(10-5)/(3-2)=5

and the slope point form of the equation is
color(white)("XXX")y-5=5(x-2)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The "slope-point form" may also appear in the form:
color(white)("XXX")y-y_2=m(x-x_2)
or
color(white)("XXX")(y-y_1)/(x-x_1)=m
or
color(white)("XXX")(y-y_2)/(x-x_2)=m
All these forms are equivalent.

Jun 2, 2016

y-5=5(x-2)

graph{y=5x-5 [-10, 10, -5, 5]}

Explanation:

The point gradient/slope form is

y-y_1=m(x-x_1)

Were y_1 and x_1 are points in which the line goes through, with x_1 being the x position and y_1 the y position which the points go through . Obviously the line goes through two of these points but lets just use (2,5) as the point.

Next, we need the gradient which is (rise)/(run). The rise between the two points are 5, with the run being 1. therefore, the gradient is 5

Now with these values, we substitute it into the equation to get an answer in point gradient/slope from.