We can find the equation when y = 360, x = 4; when y = 50, x = 2; when y = 1, x = 1 If there is a general solution, it is best

We can find the equation when y = 360, x = 4; when y = 50, x = 2; when y = 1, x = 1 If there is a general solution, it is best

Let the equation be y = ax ^ 2 + BX + C, substitute three points to get: 360 = 16A + 4B + C, 50 = 4A + 2B + C, 1 = a + B + C, solve the ternary linear equation, a = 106 / 3, B = - 57, C = 68 / 3, so the equation is y = 106 / 3x ^ 2-57b + 68 / 3