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2 years ago

If 3 is added to a certain number, the results is 15 less than three times the number. Find the number

Mathematics

1 answer:

Harman [31]2 years ago

8 0

Answer:

number = 9

Step-by-step explanation:

number = x

3 is added to a number = (x+3) result

3 times the number = 3x

15 less than three times the number = 3x-15

the results is 15 less than three times the number

x+3 = 3x -15

3x-x= 3+15

2x = 18

x=9

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SpyIntel [72]

First step, divide 6 from both sides.

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second step, subtract 1 from both sides

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Now take the square root of each side.

$\sqrt{\frac{t}{6}-1}=r$

Done!

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3 years ago

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Rama09 [41]

Answer:

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Step-by-step explanation:

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2 years ago

8x + y = -39<br> 2x - 5y = 27<br> Solve the system by elimination

Ahat [919]

Answer:

(-4, -7)

Step-by-step explanation:

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3 years ago

Gravel is being dumped from a conveyor belt at a rate of 30 ft3/min, and its coarseness is such that it forms a pile in the shap

pogonyaev

Answer:

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Step-by-step explanation:

we know that volume of a cone is given by

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It is Given that diameter equals height thus we have

$V=\frac{1}{12}\pi h^{2}h\\\\V=\frac{1}{12}\pi h^{3}$

Differentiating both sides with respect to time we get

$\frac{dV}{dt}=\frac{1}{12}\pi \frac{dh^{3}}{dt}\\\\\frac{dV}{dt}=\frac{1}{12}\pi(3h^{2}\frac{dh}{dt})$

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2 years ago

A machine cuts 25 circuit boards every 5 minutes. What is the unit rate of production for the machine?

Sladkaya [172]

Answer:

B- 5/1 boards/minutes

Step-by-step explanation:

<u>Unit rate is the number of circuit boards a minute:</u>

25 boards every 5 minutes >>
25/5 boards every 5/5 minutes >>
5/1 boards/minutes

Correct choice is B

3 0

2 years ago