Maths Question

Question

In which graph do the plotted points lie on the line y = 1/2x + 1?

Answer 1

The slope-intercept form of the equation of a line looks like this:    y= mx + b

   where

      m is the slope (that is, the slant, the grade, the incline; the slope is sometimes called "rise over run"

          because it is (increase in y-values) / (increase in x-values)

         Positive slope slants "up" going from left to right; a slope of 1 is 45 degrees.

         Negative slope slants "down" going from left to right; a slope of -1 is 45 degrees going down

             (that an exciting water slide or ski slope, but mild for a roller coaster)

      The point (0,b) is the y-intercept; it is the point where x=0;

             it is the point where the line crossed the y-axix

 

y = (1/2)x + 1

    has a slope of (+1/2).  That is, going up 1 for each 2 going right (a mild incline).

    has a y-intercept at the point (0,1)

 

All points on this line fit this format:     ( x, (1/2)x+1)

     Here are some points on the line:

           (0,1)

           (-2, 0)      this is the x-intercept, the point where y=0

           (4,3)

           (10,6)

 

Notice, when plotting, that two points determine a line.