Question

What is the equation of this graphed line?

Answer 1

y = -
`(1)/(3)` x - 5

Explanation:

The equation of a line in slope- intercept form is

y = mx + c ( m is the slope and c the y- intercept )

Calculate m using the slope formula

m = (y₂ - y₁ ) / (x₂ - x₁ )

with (x₁, y₁ ) = (- 6, - 3) and (x₂, y₂ ) = (6, - 7)

m =
`(-7+3)/(6+6)` =
`(-4)/(12)` = -
`(1)/(3)`

Note the line crosses the y- axis at (0, - 5) ⇒ c = - 5

y = -
`(1)/(3)` x - 5 ← equation of line