SOLUTION: If you had to make an equation in slope-intercept form (y=mx+b) when given two coordinates, how would you do so without making a graph?

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Question 827743: If you had to make an equation in slope-intercept form (y=mx+b) when given two coordinates, how would you do so without making a graph?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
A couple ways to do it. You can use slope and its formula. You could instead, form two equations using the two points and have a system of two simultaneous equations, and solve the system for the unknown constants, m and b.

One example, very general, (u,v) and (p,r), the given points.
m=%28r-v%29%2F%28p-u%29, which you might want to compute if using example with known coordinates.
From y=mx+b, you can solve for b, getting b=y-mx.
Use either given point for a better formula for b.
b=v-%28%28r-v%29%2F%28p-u%29%29u;
and use this "value" of b to more simply write the y=mx+b form of equation, assuming you wanted the slope-intercept form.