Use the point-slope formula.

Question

Find the equation of the line that contains the point whose coordinates are (6, 3) and has slope −1.

Answer 1

B = y - mx

= 3 - (-1)(6)

= 3 - -6

= 3 + 6

= 9

y = (-1)x + 9

-x + 9

Answer 2

Point slope form is y - y₁ = m(x - x₁).

For example, if you wanted the equation of the line that contains (0,0) with slope -1/3 it would be

y - 0 = -(1/3)*(x - 0)

or y = -(1/3)x