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3 years ago

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Shawna needs to buy some pencils and an eraser. She can spend no more than $8. The eraser costs $1 and the pencils cost $0.25 ea

ch. Write an inequality to to find x, the number of pencils Shawna buys.
A) .25x + 1 ≤ 8
B) .25x + 1 < 8
C) .25x + 1 ≥ 8
D) .25x + 1 > 8

1 answer:

madreJ [45]3 years ago

4 0

The correct answer is A

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yaroslaw [1]

<span>9r - 2 = 16

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You have 2000 grams of substance A which has decay constant 0.03, and you have 3000 grams of substance B, which has decay consta

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Answer:

If you have a quantity X of a substance, with a decay constant r, then the equation that tells you the amount of substance that you have, at a time t, is:

C(t) = X*e^(-r*t)

Now, we know that:

We have 2000g of substance A, and it has a decay constant of 0.03 (i assume that is in 1/year because the question asks in years)

And we have 3000 grams of substance B, with a decay constant of 0.05.

Then the equations for both of them will be:

Ca = 2000g*e^(-0.03*t)

Cb = 3000g*e^(-0.05*t)

Where t is in years.

We want to find the value of t such that Ca = Cb.

So we need to solve:

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e^(-0.03*t) = (3/2)e^(-0.05*t)

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Ln(e^(t*0.02)) = Ln(3/2)

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3 years ago

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Svetlanka [38]

183.75 because if you did $1470 then divided it by 8 it would =183.75

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3 years ago

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Answer:

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Step-by-step explanation:

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3 years ago

If m(x)=x+5/x-1 and n(x)=x-3 which function has the same domain as (m•n)(x)

worty [1.4K]

Consider the functions m and n:

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so if we want the function to produce c, we just set x=3+c, check:

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so let n(x)=a, consider m(a):

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is all Real numbers except 4.

Check: letting x be 4, would mean n(4)=4-3=1

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3 years ago