How do you write an equation of a line that passes through (4,9) , (-2,-6)?

1 Answer
Faizan B.
Apr 3, 2015

I will use the point-slope form of a line (y-y_1=m(x-x_1)):

Point 1 will be (4,9)
Point 2 will be (-2,-6)

Calculating the slope: m=(∆y)/(∆x)=(y_2-y_1)/(x_2-x_1)=(9-(-6))/(4-(-2))=(9+6)/(4+2)=15/6=(3(5))/(3(2))=color(red)(5/2)

So: y-(9)=(5/2)(x-4)

Now, I will transform the equation from point-slope to slope-intercept (y=mx+b) form. Remember, changing the form of a line's equation does not change the line. It simply rewrites the variables in a different way.

y-(9)=(5/2)(x-4)
y=(5/2)(x-4)+9
y=5/2x-20/2+9
y=5/2x-10+9
y=5/2x-1

Related questions
See all questions in Write an Equation Given Two Points
Impact of this question
911 views around the world
You can reuse this answer
Creative Commons License