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4 years ago

I don’t understand this one

Mathematics

1 answer:

Masja [62]4 years ago

5 0

Answer:

see below

Step-by-step explanation:

Put -1 where x is in each expression and evaluate it.

You will find that the expression is zero when the numerator is zero. And you will find the numerator is zero when it has a factor that is equivalent to ...

(x +1)

Substituting x=-1 into this factor makes it be ...

(-1 +1) = 0

Evaluating the first expression, we have ...

$\dfrac{4(x+1)}{(4x+5)}=\dfrac{4(-1+1)}{4(-1)+5}=\dfrac{4\cdot 0}{1}=0$

This first expression is one you want to "check."

You can see that the reason the expression is zero is that x+1 has a sum of zero. You can look for that same sum in the other expressions. (The tricky one is the one with the factor (x -(-1)). You know, of course, that -(-1) = +1.)

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A portion of a map with cities a and b is shown.The map uses a scale of 1 inch to 30 miles. A new map has a scale of 2 inches=15

Alina [70]

Answer:

22.5miles

Step-by-step explanation:

For Map 1;

1 inches = 30miles

For Map 2:

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1 inches = x

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x = 7.5miles

This means that 1 inch represents 7.5miles on Map 2'

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4 years ago

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Murrr4er [49]

Answer:

Step-by-step explanation:

The equation is in y=mx+b form. M is the slope. In this equation, -1/2 is m.

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3 years ago

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A spring has natural length 24 cm. Compare the work W1 done in stretching the spring from 24 cm to 34 cm with the work W2 done i

Scilla [17]

Answer:

From the analysis W1=W2.

they are directly related

Step-by-step explanation:

the work-done in stretching a spring can be expressed as

$W=\frac{1}{2}kx^2$

where k= spring constant

x= change on length of spring

Hence for W1

Given data

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solving in terms of k we have

$W=\frac{1}{2}k*10^2\\\W=\frac{1}{2}k*100\\\W=50k$

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x= 44-34= 10 cm

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3 years ago

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Y_Kistochka [10]

Answer:

14/20.

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There are 20 socks in the drawer.

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