y = 5-days-stock / 30-days-stock
x1 = date = timestamp / 1000 * 24 * 60 * 60
x2 = gold
x3 = silver
x4 = Dollar

y = sum(a1 * xn)

an may equal to 0.5
an my equal to an*xn
an may equal to an*xn*xn
an may equal to (an + b/xn)

Machine Learning can solve the an?