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3 years ago

Solve 3x+2y=7 and x-4y=-21 by using any method

Mathematics

1 answer:

kupik [55]3 years ago

8 0

Answer:

(- 1, 5 )

Step-by-step explanation:

Using the method of substitution.

Given the 2 equations

3x + 2y = 7 → (1)

x - 4y = - 21 → (2)

Rearrange (2) expressing x in terms of y by adding 4y to both sides.

x = 4y - 21 → (3)

Substitute x = 4y - 21 into (1)

3(4y - 21) + 2y = 7 ← distribute and simplify left side

12y - 63 + 2y = 7

14y - 63 = 7 ( add 63 to both sides )

14y = 70 ( divide both sides by 14 )

y = 5

Substitute y = 5 into (3)

x = (4 × 5) - 21 = 20 - 21 = - 1

Solution is (- 1, 5 )

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What is the greatest common factor of 4 and 12?

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Answer:

Step-by-step explanation:

4 : 1, 2,4

12 :1, 2, 3, 4, 6, 12

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3 years ago

Read 2 more answers

Which option below best describes the maximums of these two functions? Function g has the greater maximum of 2. Functions g and

MissTica

Answer:

salak

Step-by-step explanation:

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2 years ago

Trash Cans: Elliot's family has a cylinder shaped trash can. It takes the family a few days to fill the trash can up. Elliot wan

Elza [17]

The volume of cylinder shaped trash can is 4698 cubic inches, if the trash can has a height of 24.90 inches and a diameter of 15.50 inches.

Step-by-step explanation:

The given is,

Trash can has a height of 24.90 inches

Diameter of 15.50 inches

Step:1

Formula to calculate the volume of cylinder,

$Volume, V = \pi r^{2} h$ .............................(1)

Where, r - radius of cylinder

h - Height of cylinder

From given,

h - 24.90 inches

D - 15.50 inches

Diameter to radius conversion,

$Radius, r = \frac{d}{2}$

$= \frac{15.50}{2}$

r = 7.75 inches

Equation (1) becomes,

$V = \pi (7.75^{2} )(24.90)$

$= \pi (60.0625)(24.90)$

$=\pi (1495.556)$

$=(3.1416) (1495.556)$ (∵ $\pi = 3.1416$ )

= 4698.42

≅ 4698 cubic inches

Volume of trash can, V = 4698 cubic inches

Result:

The volume of cylinder shaped trash can is 4698 cubic inches, if the trash can has a height of 24.90 inches and a diameter of 15.50 inches.

6 0

3 years ago

Joseph has a job walking dogs and gets paid per dog. He needs to walk 45 dogs to earn enough money to pay for his soccer team fe

rusak2 [61]

Using proportions, it is found that it will take him 22.5 hours to walk the 45 dogs.

<h3>What is a proportion?</h3>

A proportion is a fraction of a total amount, and the measures are related using a rule of three. Due to this, relations between variables, either direct or inverse proportional, can be built to find the desired measures in the problem.

He walks 3 dogs in 1 hour and 30 minutes, we means that the time in hours it takes for him to walk a dog is:

t = 1.5/3 = 0.5 hours.

Hence the time it will take him to walk 45 dogs is given by:

45 x 0.5 = 22.5 hours.

More can be learned about proportions at brainly.com/question/24372153

#SPJ1

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1 year ago

Given six memory partitions of 300 kb, 600 kb, 350 kb, 200 kb, 750 kb, and 125 kb (in order, how would the first-fit, best-fit,

NNADVOKAT [17]

Answer:

Step-by-step explanation:

first fit:

115 -> 300

500-> 600

358 -> 750

200 -> 350

375 -> not able to allocate

Best fit:

115 -> 125

500 -> 600

358 -> 750

200 -> 200

375 -> not able to allocate

worst fit:

115 -> 750

500 -> 600

358 -> not able to allocate

200 -> 350

375 -> not able to allocate

6 0

3 years ago