40 points and the brainliest. quick 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 function with a y-intercept of 8,400 and a vertex of (500, 15900) x= number of helmets y = amount in dollars which system models this situation? a) y = 26x and y = 8,400(x-500)2+15,900 b) y = 26x and y = -0.030(x-500)2+15,900 c) y = x/26 and y = -0.030(x-500)2+15,900 d) y = x/26 and y =8,400(x-500)2+15,900

Given from the question
Vertex
(h,k) = (500, 15900)
One of the points on the graph
(x,y) = (0,8400)

FIRST PART: Find the quadratic function
We can find the quadratic function by this formula
y = a (x - h)² + k

Input the numbers to the formula, to find the value of a
y = a (x - h)² + k
8400 = a(0 - 500)² + 15900
8400 = a (500)² + 15900
8400 = 250000a + 15900
-250000a = 15900 - 8400
-250000a = 7500
a = 7500/-250000
a = 0.03

Submit a to the formula
y = a (x - h)² + k
y = 0.03 (x - 500)² + 15900
(This is the quadratic function)

SECOND PART: Find the linear function
the total cost = cost each helmet × the number of helmet
y = 26x

SO, THE ANSWER IS OPTION B