



 
Hi Swathi, If you have a quadratic equation of the form $y = a x^2 + b x + c$ then its graph is a parabola. If you can factor the right side to obtain $y = A (x  h)(x  k)$ then $x = h$ and $x = k$ both yield $y = 0.$ Thus the graph passes through $(h, 0)$ and $(k, 0).$ The converse is also true. A quadratic (parabola) which passes through $(h, 0)$ and $(k, 0)$ has the form $y = A (x  h)(x  k).$ Form the given information you know $h = 0$ and $k = 15.$ All that remains is to find $A.$ Draw a diagram of the arch. What is the value of $x$ where the arch has its peak? Is $A$ positive or negative? What is the value of A? Write back if you need more help,
 


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