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View Full Version : writing equations of line with given slopes, etc.

tseday871221
01-11-2007, 01:25 AM
I need help writing this in the form Ax+Bx=C. (Is this equation the same as Y=Mx+b?)

1) Find the equation of the line with slope -2/5 and passing through (2,0)

2) Find the equation of the line passing through (-2,0) and (-6, 5)

stapel
01-11-2007, 10:12 AM
No, "y = mx + b" is not the same as "Ax + By = C", since the former has the variables on opposite sides of the "equals" sign, and the latter does not.

1) You are given a point and a slope. Try plugging this into the point-slope formula they gave you. Simplify. Then move both variable terms onto one side of the equation, with the constant term on the other. If there are any fractions, multiply through by an appropriate value to make all the numbers into whole numbers.

2) Plug the two points into the slope formula they gave you. Then take that slope and one of the original points (it doesn't matter which), and follow the same process as in (1).