
William W. answered 11/30/21
Math and science made easy - learn from a retired engineer
Initially, you can write the equation of the line easily by using the point-slope form:
y - y1 = m(x - x1) where "m" is the slope and (x1, y1) is a point. So, since m = 3/4 and (x1, y1) = (-8, 4) then the equation of the line is y - 4 = 3/4(x - -8)
Now, use algebra to modify the form. First simplify then multiply it out to get:
y - 4 = 3/4(x - -8)
y - 4 = 3/4(x + 8)
y - 4 = 3/4x + 6 then add 4 to both sides:
y = 3/4x + 10 then multiply both sides by 4:
4y = 3x + 40 then subtract 4y from both sides:
0 = 3x - 4y + 40 then subtract 40 from both sides to get:
-40 = 3x - 4y and switch it around to get:
3x - 4y = -40 meaning A = 3, B = -4, and C = -40