SOLUTION: I do not understand how to write an equation of a line passing through a point with an already given slope. Ex. (3,-4); m=2/3

Algebra ->  Graphs -> SOLUTION: I do not understand how to write an equation of a line passing through a point with an already given slope. Ex. (3,-4); m=2/3       Log On


   

Question 245825: I do not understand how to write an equation of a line passing through a point with an already given slope.
Ex. (3,-4); m=2/3
Answer by dabanfield(803) About Me  (Show Source):
You can put this solution on YOUR website!
The equation of a line in slope intercept form is:
y = m*x + b where m is the slope and b is the value of y where the line crosses the y-axis (this is actually the value of y when x is zero).
Since you know the slope m in this case is 2/3 you have:
y = (2/3)*x + b
Since the point (3,-4) is a point on the line we know that:
-4 = (2/3)*3 + b
-4 = 2 + b
-2 = b
Substituting -2 for b in the equation above we get:
y = (2/3)*x -2 for the equation of the line