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how would u solve and graph -x+2y=17

We are dealing with Parallel and Perpendicular lines and our teacher wants us to graph it and tell the difference between the two and use a graph on every one


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Nicole C. | Increase confidence in math and science, chemistry, algebra IIIncrease confidence in math and science,...
4.9 4.9 (167 lesson ratings) (167)

Get y by itself first (get it into slope-intercept form)

  -x + 2y = 17

  +x          +x

  2y = x + 17

  2         2

  y = x  +  17

        2       2

Remeber slope-intercept is:   y = mx + b, and m = slope, and b = y-int

   for your equation:  m = 1/2,  b = 17/2 = 8.5

On your graph paper:

  Plot the point (0,8.5)  --> your y-int is where the graph crosses the y-axis, the y-axis is where x is zero

  From that point move up 1 (top of your slope fraction - up because it is positive), then right 2 (bottom of your slope fraction)


Regarding parallel and perpendicular lines:

Parallel lines will have the same slope and never touch

   Ex:   y = 3x + 2   and   y = 3x - 5

Perpendicular lines will have slopes be the opposite reciprocal and will touch once at a 90 degree angle

   Ex:  y = 3x + 2   and y = -(1/3)x -5

   Opposite Reciprocal:

      Opposite means their signs are different, one has to be positive and one negative

      Reciprocal:  flip the fraction up-side-down.  A 3x has a slope of 3 which is equal to 3/1. 

                       The reciprocalof this is 1/3