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It would be -1/2 because the formula to find slope (rate of change) is (y2-y1)/(x2-x1) and in this case it would be (4.5-2)/(-3--2) which simplifies to (2.5)/(-5) which is -1/2
Answer:

Step-by-step explanation:
u = Initial velocity of baseball
= Angle of hit = 
x = Displacement in x direction = 400 ft
y = Displacement in y direction = 15 ft
= Height of hit = 2.5 ft
= g = Acceleration due to gravity = 
t = Time taken
Displacement in x direction

Displacement in y direction

The minimum initial velocity needed for the ball to clear the fence is 
Can you give the data please?