Find an equation of the line described. Leave the solution in the form Ax + By = C. The line has slope m = − 4/5 and contains (0, 8).

Question

Find an equation of the line described. Leave the solution in the form Ax + By = C.

The line has slope m = − 4/5

and contains (0, 8).

Answer 1

first write in point intercept form: y - y1 = m(x - x1) where m is slope and (x1,y1) is a point on the line:

y - 8 = (-4/5) ( x - 0)

then use algebra to put into general form:

y - 8 = -(4/5)x

(4/5)x + y = 8

multiply both sides by 5 to free equation of denominators:

4x + 5y = 40