Question

What is the equation for the line?

Answer 1

y = - 2x - 4

Explanation:

the equation of a line in slope- intercept form is

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

To calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (- 2, 0) and (x₂, y₂ ) = (0, - 4) ← 2 points on the line

m =
`(-4-0)/(0+2)` =
`(-4)/(2)` = - 2

not the line crosses the y-axis at (0, - 4) ⇒ c = - 4

y = - 2x - 4 ← equation of line