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3 years ago

How to solve #4 using substitution/ elimination method

Mathematics

1 answer:

kolezko [41]3 years ago

3 0

3x+y = 4
x+y= 2 multiply all the elements of (x+y) by -1 & then add it up to the 1st equation
3x+y=4
-x-y =-2
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2x+0y =2 ==> x=2/2 =1 & replace x=1 by its value in any of the equation & you will get the value of y=1

2) 3x+y = 7
x+2y = 4
Follow the same methodology as before, but to eliminate y, multiply the 1st equation by (-2) and you will get x=2 & y=1

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Solve each system by elimination. 3x - 2y = 1 2x + 2 y = 14

Paha777 [63]

Add 3 and 12 , cancel -2 y+2y and and add 14 and 14
3x-2y=14
12x+2y=14
15x=28
Divide both sides by 15
X=28/15
3x 28/15 -2y=14
Y=-21/5
(X,y)=28/15, -21/5
3x 28/15 -2x(-21/5)=12x 28/15 +2x(-21/5)=14
14=14=14
(x, y)=(28/15, -21/5) is the answer

6 0

2 years ago

Which one of the following is always true?a. The coefficient of variation measures variability in a positively skewed data set r

Tom [10]

Answer:

C. The coefficient of variation is a measure of relative dispersion that expresses the standard deviation as a percentage of the mean, for any data on a ratio scale and an interval scale

Step-by-step explanation:

Th Coefficient of Variance is a measure of dispersion that can be calculated using the formula:

$CV = \frac{\sigma_{x} }{\mu_{x} } * 100%$

Where $\sigma{x}$ is the Standard Deviation

and $\mu_{x}$ is the sample mean

From the formula written above, it is shown that the Coefficient of Variation expresses the Standard Deviation as a percentage of the mean.

Coefficient of variation can be used to compare positive as well as negative data on the ratio and interval scale, it is not only used for positive data.

The Interquartile Range is not a measure of central tendency, it is a measure of dispersion.

3 0

3 years ago

The family wants to determine if they can drive to the national park using Just one tank of gas in their car. Determine whether

Nataliya [291]

Answer:

The Fullers can reach the national park

Step-by-step explanation:

<u><em>The complete question is</em></u>

The Fuller family wants to drive to a national park. Some information about their trip is given in the table below.

Distance to national park 515 miles

Car’s gas tank capacity 20 gallons

Average gas mileage for car 26 miles per gallon

The family wants to determine if they can drive to the national park using just one tank of gas in their car. Determine whether the Fullers can reach the national park. Show your work or explain your answer.

we know that

The Average gas mileage for the car is 26 miles per gallon

That means

With 1 gallon the car runs 26 miles

using a proportion

Find out how many miles the car runs with 20 gallons (one tank of gas)

$\frac{26}{1}\ \frac{miles}{gallon}=\frac{x}{20}\ \frac{miles}{gallons}\\\\x=26(20)\\\\x=520\ miles$

Compare with the distance to the national park

$520\ miles>515\ miles$

therefore

The Fullers can reach the national park

7 0

3 years ago

Allie bought a 5-pound bag of trail mix. She gave 12 ounces of trail mix to Justin. Then she put the rest of the trail mix into

trapecia [35]

To solve this problem, you will first want to convert 5 pounds into ounces. To do this, first determine how many ounces is in 1 pound.

There are 16 ounces in 1 pound, so to convert 5 pounds into ounces, you simply have to multiply 5 × 16. This will give you 80 ounces total.

Allie give 12 ounces away, so you must first subtract 12 ounces from your total (80 ounces). 80 - 12 gives us 68 ounces.

Allie then divides the trail mix up into 4 ounce portions. To figure out how many small bags she can make, you simply divide your new total (68 ounces) by 4.

68 ÷ 4 = 17

Allie made 17 small bags.

3 0

3 years ago

What is b + 3 (b - 2) = 2

Lunna [17]

Answer:

b=2

Step-by-step explanation:

b+3b - 6 =2

4b=8

b=2

Have a good day

4 0

2 years ago

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