f(x) = x^(2) - 5 * x + 4
g(x) = -0.5 * x^(2) + 1.5 * x - 2
h(x) = 2.5 + 4 * x^(2)
l(x) = -x^(2) - 2 * x
m(x) = 13.5 + 1.5 * x^(2) + 9 * x
p(x) = -0.5 * x^(2) + 4 * x - 8
a = 1 (slider from -4 to 4, step 0.5)
b = -5 (slider from -6 to 10, step 0.5)
c = 4 (slider from -10 to 15, step 0.5)
t(x) = a * x^(2) + b * x + c
ac: a * c
Δ: b^(2) - 4 * ac
Equation: a * x^(2) + b * x + c = 0