Matematika feladatok
  • via_mala
    #457
    n-szög szögösszege = 180*(n-2)
    n >= 3

    180*(n-2) = 100*n + 10*n*(n-1)/2
    180*n - 360 = 100*n + 5*n^2 - 5*n
    180*n - 360 = 95*n + 5*n^2
    0 = 5*n^2 - 85*n + 360

    n1,2 = (85 +- sqrt(85^2 - 4*5*360))/(2*5)
    n1,2 = (85 +- 5)/10
    n1 = 90/10 = 9
    n2 = 80/10 = 8