y = 3x - 1
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y-intercept )
here slope m = 3
y = 3x + c ← is the partial equation
to find c substitute (- 2, - 7 ) into the partial equation
- 7 = - 6 + c ⇒ c = - 7 + 6 = - 1
y = 3x - 1 ← equation in slope- intercept form