Section 4.3

Graphing Intercepts

X-intercept: Where the line crosses the x-axis (?,0)

Y-intercept: Where the line crosses the y-axis (0,?)

Substitution: Replacing a variable with a number or vice versa

  2x + 7y = 28                1.) Find intercepts: substitute 0 in for x and y

2x + 7(0) = 28                2.) Graph those 2 points ONLY

          2x = 28

          / 2 = / 2                

            x = 14

   2x + 7y = 28

2(0) + 7y = 28

           7y = 28

           / 7 = / 7

             y = 4