What is the equation of the line that passes through (3, —3) and a slope of 3?

1 Answer
Nov 10, 2015

Use the gradient and one point equation and rearrange into the form y=mx+c

Explanation:

The equation of a line can be found if the gradient or 'slope' and one point on the line is know can be found with the equation: y-y_1 = m(x-x_1) when you have the coordinates (x_1,y_1) and the gradient m.

Substituing in the values for your case we get: y-(-3) = 3(x-3)

Cleanining up the two negatives and expanding the brackets on the right hand side we get: y+3 = 3x-9

Now we take away 3 from both sides to get it in the form y=mx+c

This results in the equation and answer to your question: y = 3x-6