if a football player passes a football from 4 feet off the ground with an initial velocity of 36 feet per second, how long will it take the football to hit the ground? use the equation h = −16t^2 + 6t + 4. round your answer to the nearest hundredth.
a) 0.72
b) 0.65
c) 0.35
d) 0.27

  A)  0.72

Step-by-step explanation:

You want to find t when h = 0, so you're solving ...

  0 = -16t^2 +6t +4

The quadratic formula tells you the solution is ...

  t = (-b +√(b² -4ac))/(2a) . . . . . . where you have a=-16, b=6, c=4

  t = (-6 -√(36 -4·(-16)·4))/(2(-16)) = (-6 -√292)/-32

  t ≈ 0.7215 ≈ 0.72 . . . . seconds

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Comment on the problem statement

It appears the velocity number of 36 ft/s is irrelevant, as the equation tells you the initial upward speed of the ball is 6 ft/s.

c

step-by-step explanation:

system of linear equation

step-by-step explanation:

as given in the data

a= 20 , b= -12

let us suppose that it is a straight line equation

now we know the formula for the system of linear equation

b= ma + c )

here m is slope of a straight line which is equal to formula

m=   (ii)

and here c is a constant

now putting the value of a and b in equation (ii)

m=

m=

putting the value of a,b and m in equation (i) gives us

-12 = + c

-12=-12 + c

adding 12 to both sides

-12 +12 = -12 +12 +c

0 =c

or c=0

as the value of the constant is zero which gives us that it is a linear equation and this order pair satisfies the system of linear equations.