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An object is launched from a height of 129 feet above the ground. A quadratic function \( f \) models the height above the ground, in feet, of the object \( t \) seconds after it is launched. According to the model, 2 seconds after the object is launched, it reaches a maximum height of 193 feet above the ground.
Which equation defines \( f \)?

What is the y-intercept of the graph of \( y=x^2+38 \) in the xy-plane?

 A quadratic model gives the predicted instantaneous rate of change, in bacteria per hour, of a bacteria population as a function of the population size. According to the model, the predicted instantaneous rate of change is 0 bacteria per hour for a population size of 0, and the maximum predicted instantaneous rate of change is 0.200 bacteria per hour for a population size of 7,000. Based on this model, what is the predicted instantaneous rate of change, in bacteria per hour, of the bacteria population for a population size of 700?

The graph gives the estimated revenue, in dollars, for a company when the price of the company's product is x dollars. What does the y-value of the vertex of the graph represent in this context?

\( h\left(t\right)=-16t^2+b \) 
The function h estimates an object's height, in feet, above the ground t seconds after the object is dropped, where b is a constant. The function estimates that the object is 2,025 feet above the ground when it is dropped at t = 0. Approximately how many seconds after being dropped does the function estimate the object will hit the ground?

\( f(x)=-16x^2+99 \) 
The function \( f \)gives the estimated height, in feet, of an acorn x seconds after the acorn fell from a tree. Based on the function, what is the estimated height, in feet, of the acorn before it fell from the tree?

What is an x-intercept of the graph of \( y=x^2-25 \)  in the xy-plane?

For the quadratic function \( f \), the table shows three values of \( x \) and their corresponding values of \( f\left(x\right) \). Which equation defines \( f \)?

An object is kicked from a platform. The equation h = —4.9t²+ 7t ＋ 9 represents this situation, where h is the height of the object above the ground, in meters,t seconds after it is kicked. Which number represents the height, in meters, from which the object was kicked?

x	f(x)
-1	10
0	14
1	20

For the quadratic function f, the table shows three values of x and their corresponding values of f(x). Which equation defines f?

The graph of \( y=2x^2+bx+c \) is shown, where b and c are constants. What is the value of bc?

An egg is thrown from a rooftop.The equation \( h=-4.9t^2+9t+18 \)  represents this situation, where h is the height of the egg above the ground, in meters, t seconds after it is thrown. According to the equation, what is the height, in meters, from which the egg was thrown?