



 
Hi Jeni, The parabola y = x^{2} has its vertex at the origin and opens upwards. To change the spread of the arms multiply by a constant a to get y = a x^{2}. Since your parabolic arch opens downwards you know that a is negative. To lift the arch so that its vertex is 4 m above the floor (the Xaxis) add 4 to the right side to get
Since the width at the floor is 3 m, the parabola must pass through (3/2, 0). Use this to find a. Now can you complete the problem? Penny  


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