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3 years ago

8

Solve the system using addition. Use pencil and paper. Explain why the addition method is a good choice for solving the system.

If you wanted to solve for x first, is the addition method still a good choice? Explain.
x-2.5y=12.5
-x+2.3y=11.9

1 answer:

raketka [301]3 years ago

5 0

Answer:

because u got to kcc=keep change change

Step-by-step explanation:

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Write the list of numbers in order from smallest to largest.<br> 0.551, 0.554 , 5/6

joja [24]

It’s already listed smallest to largest, so leave it as the answer!

6 0

3 years ago

When dividing complex numbers, why do

Kruka [31]

Answer:

Hope this helps..

Step-by-step explanation:

So when you need to divide one complex number by another, you multiply the numerator and denominator of the problem by the conjugate of the denominator. This step creates a real number in the denominator of the answer, which allows you to write the answer in the standard form of a complex number.

8 0

3 years ago

The cellular phone service for a business executive is $35 per month plus $0.40 per minute of phone use over 900 min. For amonth

Helen [10]

Answer:

1022 minutes

Step-by-step explanation:

Let x be the number of minutes the executive used the phone

There is a base charge of $35 and only minutes greater than 900 min are charged at the rate of $0.40 per minute

So total bill A = 35 + 0.4(x-900)

We know the bill was $83.80

So we can rewrite the equation as

35 + 0.4(x-900) = 83.30

and solve for x

To make it easier for computational purposes

1) Multiply both sides by 10

$35\cdot \:10+0.4\left(x-900\right)\cdot \:10=83.8\cdot \:10$

2) Perform individual multiplication

$350+4\left(x-900\right)=838$

3) Subtract 350 from both sides

$350+4\left(x-900\right)-350=838-350$

4) Simplify

$4\left(x-900\right)=488$

5) Divide both sides by 4

$\frac{4\left(x-900\right)}{4}=\frac{488}{4}$

6) Simplify

$x-900=122$

7) Add 900 to both sides to isolate x

$x-900+900=122+900$

8) Simplify to obtain x

$x=1022$

Answer: The executive used the phone for 1022 minutes that month

6 0

2 years ago

Suppose there are 20 people in a room and the mean amount of cash held by these 20 people is $14.50 per person. If two people en

leva [86]

Answer:

13.59

Step-by-step explanation:

The calculation of amount of cash in the room is shown below:-

$\$14.50 = \frac{\Sigma xi}{20}$

= 20 × $14.50

= $290

Now, the new sum is

= ∑xi + $4.00 + $5.00

= $290 + $4.00 + $5.00

= $299

Total person in the room is

= 20 + 2

= 22

So,

Mean amount of cash in the room = New sum ÷ Total person in the room

= $299 ÷ 22

= 13.59

4 0

3 years ago

You pull a sled across a horizontal frictionless patch of snow. If your pulling force is in the same direction as the sled's dis

nexus9112 [7]

Answer:

The kinetic energy of the sled is going to increase by 18.75%

Step-by-step explanation:

The work W realized by a Force F is given by:

$W=F_x*x$

Where x is the displacement and $F_x$ is the component of the force that is parallel to the displacement.

Additionally, the work is equal to the change in the kinetic energy

$W=K_f-K_i$

If your pulling force is in the same direction as the sled's displacement, we can said that: $F=F_x$

And if increases the kinetic energy of the sled by 27%, we can said that:

$K_f-K_i=0.27K_i$

So, we can formulate the following equation:

$W=F*x\\W=0.27K_i\\\\F*x=0.27K_i$ (1)

On the other hand, if the pulling force acted at an angle of 46° above the horizontal, the work is:

$W=F_x*x=Fcos(46)*x=F*x*cos(46)$ (2)

Then, replacing (1) in (2), we get:

$W=F*x*cos(46)=0.27K_i*cos(46) = 0.1875K_i$

Finally, the kinetic energy increase by 18.75% because:

$W=K_f-K_i\\W=0.1875K_i\\\\K_f-K_i=0.1875K_i$

5 0

3 years ago