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4 years ago

Use the quadratic formula to solve the equation: 0 = x2 + x - 20

Mathematics

1 answer:

Art [367]4 years ago

7 0

Answer:

(x-4)*(x+5) : x =4,-5

Step-by-step explanation:

a= 1

b= 1

c= -20

x1,2 = (-1+-(1 - (4*1*-20))^0.5)/2

x1,2 = (-1+-(1+80)^0.5)/2

x1,2 = (-1+-(81^0.5))/2

x1,2 =(-1+-9)/2

x1 = 8/2 = 4 x2 = -10/2 = -5

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3 years ago

50 points! I understand A. and B. but I would really appreciate help with C.

FromTheMoon [43]

Answer:

$51.72\text{ cells per hour}$

Step-by-step explanation:

So, the function, P(t), represents the number of cells after t hours.

This means that the derivative, P'(t), represents the instantaneous rate of change (in cells per hour) at a certain point t.

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$P'(t)=\frac{d}{dt}[6.10t^2]+\frac{d}{dt}[-9.28t]+\frac{d}{dt}[16.43]$

Move the constant to the front using the constant multiple rule. The derivative of a constant is 0. So:

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3 years ago

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stellarik [79]

Answer:

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Step-by-step explanation:

This question is fairly simple, you just have to simplify it. You are starting at already half-full, so you can keep that 1/2 in mind. Then, she adds 360 pennies to get 5/6. If you convert 1/2 into 3/6, you can see that 360 pennies fills 2/6 of the piggy bank. So now you can solve two different ways. The first, you can take 360 and multiply it by 3 to get the amount that can fit in the piggy bank, because 2 * 3 = 6 and that would make it 6/6, or 1. The other way would be to divide 360 by 2 to get 1/6 of the piggy bank, or 180. Then you can multiply 180 by 6 to get the entire amount.

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