Question

A line with a slope of –9 passes through the point (1, –9) . What is its equation in slope -intercept form?

Answer 1

Explanation:

we start with the point-slope form

y - y1 = a(x - x1)

where "a" is the slope, (x1, y1) is a point on the line, and then we simplify that equation giving us the slope-intercept form

y = ax + b

so,

y - -9 = -9(x - 1)

y + 9 = -9(x - 1)

and now simplifying this

y + 9 = -9x + 9

y = -9x