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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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I need the length of AC to the nearest 10th. If you can explain how you got it, that will be nice, but you don’t have too

Nezavi [6.7K]

Answer:

13.5

Step-by-step explanation:

$\sin 64\degree = \frac{AC}{AB}\\\\AC = AB \sin 64\degree \\\\AC = 13.481910694\\\\AC \approx 13.5$

4 0

3 years ago

Read 2 more answers

If the population of a town grew 15% up to 76,894, what was the population lest year?

frozen [14]

Let's first find the equation to find what the population went up to. X, will be the population of last year.
1.15x=76,894
Now, we need x by itself, so we need to divide both sides by 1.15.
76,894÷1.15≈66,864
There are decimals, but for this problem, hae .3478 of a person would not fit.
We can check our answer.
66,864×.15=10,029.6
10,029.6+66,864=76,893.6 (rounds up to 76,864)
So the population of the town last year was about 66,864 (66,864.3478) people.

4 0

3 years ago

A bag contains 25 balls 20 of which are blue what percentage of balls are not blue

Artist 52 [7]

Answer:

20%

Step-by-step explanation:

20/25 = blue

This means 5/25 of the balls in the bag are NOT blue

(25-20 = 5)

We need to convert 5/25 to a percentage

$\dfrac{5}{25} = \dfrac{5\times4}{25\times4}=\dfrac{20}{100}$

% = per cent

"per" means "out of"

"cent" means "one hundred"

20/100 = 20%

7 0

1 year ago

I need it now plz btw i am in middle school

Svet_ta [14]

Answer:

A)2x+7=38

2x=38-7

2x=31

x=31/2

x=15.5

B)3x-8=52

3x=52+8

3x=60

x=60/3

x=20

C)34%of 68

34/100×68

0.34×68

=23.12

7 0

2 years ago

Tom was driving 20.3 meters per second in a 45 mile per hour zone. Was Tom speeding? Explain using a unit conversion as well as

My name is Ann [436]

Answer:

Tom was speeding.

Step-by-step explanation:

The driving speed of Tom = 20.3 meters per second.

Speed allowed in the zone = 45 miles per hour zone.

Since the unit of speed allowed is given in miles per hour but the speed of tom is given in meters per second. So, first, we have to convert the meter per second into mile per hour then we can compare and find that Tom is speeding or not.

1 mile = 1609.34 meters

1 hour = 3600 second

Now convert 20.3 into mile per hour.

20.3 meters per second. = (20.3 / 1609.34)*3600 = 45.40981 mile per hour.

Since Tom’s speed is more than the allowed speed so he is speeding.

7 0

3 years ago