Question

Which equation represents a line that passes through (-9, -3) and has a slope of -6?

Answer 1

Slope-intercept form: y = mx + b

[m is the slope, b is the y-intercept or the y value when x = 0 ---> (0, y) or the point where the line crosses through the y-axis]

Since you know:

m = -6 Substitute/plug it into the equation

y = mx + b

y = -6x + b To find b, plug in the point (-9, -3) into the equation

-3 = -6(-9) + b [two negative signs cancel each other out and become positive]

-3 = 54 + b Subtract 54 on both sides

-57 = b

y = -6x - 57

Answer 2

Explanation:

Slope m = -6

Point (-9, -3)

y1 = -3 and x1 = -9

The equation is y - y1 = m(x - x1)

y - (-3) = -6[x - (-9)]

y + 3 = -6(x + 9)

y + 3 = -6x - 54

y = -6x - 54 - 3

y = -6x - 57