text: 2x^2 - x- 3 = 0\n\na = 2\nb = -1\nc = -3\n\nx = [-b +- sqrt(b^2-4ac)]/2a\nx = [-(-1) +- sqrt((-1)^2-4(2)(-3))]/2*2\nx = [1 +- sqrt(1 - (-24))]/4\nx = [1 +- sqrt(1 + 24)]/4\nx = [1 +- sqrt(25)]/4\nx = [1 +- 5]/4\n\nThus,\n\nx = [1+5]/4 or [1-5]/4\nx = 6/4 or -4/4\nx = 1.5 or -1\n\nThe *sum* of the solutions is 1.5 + -1 = .5 (or 1/2)