Question

A-line includes the points (8,9) and (9,1). What is its equation in point-slope form?

Answer 1

Answer:

$y-(9)=(-8)(x-8)$

Step-by-step explanation:

$(x_1, y_1) = (8, 9)\\(x_2, y_2) = (9,1)$

Step one: Find the slope (m)

$slope=m=\frac{rise}{run} =\frac{y_2-y_1}{x_2-x_1} = \frac{1-9}{9-8} =\frac{-8}{1} =-8$

Step two: Plug your known values into the point-slope equation

$m=-8\\y_1=9\\x_1=8$

Point-slope form is $y-y_1=m(x-x_1)$

$y-(9)=(-8)(x-8)$

If you want to convert point-slope form to general form, isolate for y.

$y-9=-8x+64\\y=-8x+73$