Final answer:
The maximum height of the diver is 12 ft.
Step-by-step explanation:
To find the maximum height of the diver, we need to determine the vertex of the quadratic equation Y= -4/9x²+24/9x+9. The x-coordinate of the vertex can be found using the formula x = -b / (2a), where a = -4/9 and b = 24/9. Plugging in these values, we get x = -24 / (2(-4/9)), which simplifies to x = 3.
Now we can substitute the value of x into the equation to find the maximum height. Plugging x = 3 into Y = -4/9x²+24/9x+9, we get Y = -4/9(3)²+24/9(3)+9. Simplifying this expression, we find Y = 12, so the maximum height of the diver is 12 ft.