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1 year ago

Show your work for -4x+3(2x-5)=31

Mathematics

1 answer:

mina [271]1 year ago

4 0

Step-by-step explanation:

$- 4x + 3(2x - 5) = 31 \\ - 4x + 6x - 15 = 31 \\ 2x - 15 = 31 \\ 2x = 31 + 15 \\ 2x = 46 \\ x = 46 \div 2 \\ x = 23$

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Solve by the elimination method. Show your work 2x – 5y = 1 3x – 4y = -2

svlad2 [7]

Hello,

2x-5y=1 |3|4
3x-4y=-2|-2|-5
------------------------

-7y=7 ==>y=-1
-7x=14==>x=-2

sol={(-2,-1)}

3 0

3 years ago

One watering system needs about three times as long to complete a job as another warning system when both systems operate at the

algol13

Answer:

One watering system requires 36 minutes to complete the job alone while another watering system requires 12 minutes to complete the job alone.

Step-by-step explanation:

Given:

Both the system can complete the job = 9 minutes

We need find the time required by each system to do the job.

Solution:

Let the time required by another watering system to complete the job be 'x' mins.

Now given:

One watering system needs about three times as long to complete a job as another watering system.

Time required by one watering system = $3x$

Rate to complete the job by another watering system = $\frac{1}{x}\ job/min$

Rate to complete the job by One watering system = $\frac{1}{3x}\ job/min$

Rate at which both can complete the job = $\frac{1}{9}\ job/min$

So we can say that;

Rate at which both can complete the job is equal to sum of Rate to complete the job by another watering system and Rate to complete the job by One watering system.

framing in equation form we get;

$\frac{1}{x}+\frac{1}{3x}=\frac19$

Now taking LCM to make the denominator common we get;

$\frac{1\times3}{x\times 3}+\frac{1\times1}{3x\times1}=\frac19\\\\\frac{3}{3x}+\frac{1}{3x}=\frac19\\\\\frac{3+1}{3x}=\frac{1}{9}\\\\\frac{4}{3x}=\frac{1}{9}$

By Cross multiplication we get;

$4\times9 =3x\\\\3x =36$

Dividing both side by 3 we get;

$\frac{3x}{3}=\frac{36}{3}\\\\x=12\ min$

Time required by One watering system = $3x =3\times 12 =36\ min$

Hence One watering system requires 36 minutes to complete the job alone while another watering system requires 12 minutes to complete the job alone.

6 0

3 years ago

16 increased by twice a number is -24

wlad13 [49]

X-the number

16 + 2x = -24 |subtract 16 from both sides

2x = -40 |divide both sides by 2

x = -20

Answer: The number is -24

8 0

3 years ago

What is the distributive property for 9−12x+6y=

Ulleksa [173]

Because there are no parentheses, I'm assuming you're asking for how to factor this using the GCF, which can be done like so:

9−12x+6y

Factor a 3 out of this expression.

3(3 - 4x + 2y)

The expression has been simplified using the distributive property in reverse.

8 0

3 years ago

describe the relationship between n and 4 that will make the value of the expression 7× n/4 greater than 7

Norma-Jean [14]

So set up an equation!

7* n/4 > 7

So trying to get the variable alone...

n/4 > (7/7) aka 1
n> 1*4
n> 4

Try it out!

7* 6/4 = 42/4 = 21/2= 10 and 1/2

It is greater than 7

7 0

3 years ago