What would the standard form of a line be with the points (3,3) and (-6,-6)?
The point-slope form is: y - y1 = m(x - x1)
If you call the point (3,3) = (x1,y1) and (-6,-6) = (x2, y2)
and if you find the slope: m = (y2 - y1) / (x2 - x1)
m = (-6 - 3) / (-6 - 3) = -9 / -9 = 1
Substitting these into the point-slope form: y - 3 = 1(x - 3)
simplifying: y - 3 = x - 3
-x + y = 0
x - y = 0
The point-slope form is: y - y1 = m(x - x1)
If you call the point (3,3) = (x1,y1) and (-6,-6) = (x2, y2)
and if you find the slope: m = (y2 - y1) / (x2 - x1)
m = (-6 - 3) / (-6 - 3) = -9 / -9 = 1
Substitting these into the point-slope form: y - 3 = 1(x - 3)
simplifying: y - 3 = x - 3
-x + y = 0
x - y = 0