a = 1 (slider from -5 to 5, step 0.1)
b = -0.2 (slider from -5 to 5, step 0.1)
c = -1 (slider from -5 to 5, step 0.1)
d: y = (a * x^(2)) + (b * x) + c
texto1: "y = " + a + " x² + " + b + " x + " + c + ""