The right answer for the question that is being asked and shown above is that: "y = x/26 and y = -0.030(x-500)2+15,900." A company plans to sell bicycle helmets for $26 each. The company's business manager estimates that the cost, y, of making x helmets is a quadratic <span>function with a y-intercept of 8,400 and a vertex of (500, 15,900).</span>
Well, the interest literally mean the amount that add up to your previous capital that you invest in the past. If you invest an amount of money and get an interest revenue out of it, the amount of your capital will be increased , not decreased