Question

A trend line passes through the points (-4, 9) and (1, -1). What is the equation of the trend line? (y=mx+b, no spaces)

Answer 1

9514 1404 393

Answer:

y = -2x +1

Explanation:

It is often convenient to start with a 2-point form of the equation for a line:

y = (y2 -y1)/(x2 -x1)(x -x1) +y1

y = (-1-9)/(1-(-4))(x -(-4)) +9 . . . . fill in the given points

y = -10/5(x +4) +9 . . . simplify a bit

y = -2x +1