Answer:
x= -6
Step-by-step explanation:
Answer: Our Cost function is discontinuous at every integer after x>10.
Step-by-step explanation:
Since we have given that
For the first 10 minutes , the service charges = $0.30
Let the number of additional minute be 't'.
Amount charge for each additional minute = $0.05
Using the greatest integer function:
So, Cost C of a call in terms of time 't' minutes would be

As we know that Greatest integer is discontinuous at every integer.
So, our Cost function is discontinuous at every integer after x>10.
I think it’s b the water is 2.2 meters below the ground floor. Sorry if I’m wrong.
Let the width be "x" cm.
Then the length is "x+12" cm
And the area = x(x+12) = x^2+12x cm^2
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Change the dimensions:
width = "x-2" cm
length = "x+10" cm
New area = (x-2)(x+10) = x^2 + 8x - 20 cm^2
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Equations :
Old area - New area = 108 cm^2
x^2+12x -(x^2 + 8x - 20) = 108
4x + 20 = 108
4x = 88
x = 22 cm (original width)
x+12 = 24 cm (original length)