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Suppose you have a straight line containing the points (-1,7) and (2,-5).

  1. What is the slope of the line?


  2. Find an equation for the line.

    Using the point-slope form: y-7=-4(x+1). Alternative, y-(-5)=-4(x-2). In either case, the formula can be simplified to y=-4x+3 if you wish.

  3. What is the x-intercept of the line?

    Setting y=0, we get 0=-4x+3, 4x=3, x=3/4. So the x-intercept is the point (3/4,0).

  4. What is the y-intercept of the line?

    Setting x=0, we get y=3. So the y-intercept is the point (0,3).

Carl Lee
Fri Sep 11 12:53:01 EDT 1998