Question

The equation of the line that goes through the points (−6,2) and (-7,-7) can be written in general form Ax+By+C=0 where

Answer 1

A = 9, B = - 1, C= 56

obtain the equation in ' slope-intercept form'

y = mx + c → ( m is the slope and c the y- intercept)

calculate m using the ' gradient formula'

m = (- 7 - 2)/(- 7 + 6) = (-9)/(-1) = 9

partial equation is y = 9x + c

to find c substitute either of the 2 points into the equation.

using (- 6, 2) then

2 = - 54 + c ⇒ c = 2 + 54 = 56

y = 9x + 56 → slope-intercept equation

subtract y from both sides

0 = 9x - y + 56 → general form

with A = 9, B = - 1, C = 56