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2 years ago

Substitution method...need help.. started but cant finish

Mathematics

1 answer:

trapecia [35]2 years ago

8 0

Solve either equation for either variable. Since the second one has y on its own, the easiest choice is to solve that for y.

-5x + y = 13 ⇒ y = 5x + 13

Now substitute this into the other equation to eliminate y and rewrite it entirely in terms of x :

-3x + 3y = 3 ⇒ -3x + 3 (5x + 13) = 3

Simplify and solve for x :

-3x + 15x + 39 = 3

12x = -36

x = -3

Substitute this into either original equation to solve for y. Plugging x = -3 into the first equation would give

-3 (-3) + 3y = 3

9 + 3y = 3

3y = -6

y = -2

So the solution to the system of equations is (x, y) = (-3, -2).

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Hi everyone the first person to answer this right gets 40 points

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Balance after 4 years is $1440

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3 years ago

Eleven more than five times a number is equal to the difference between −38 and twice the number. Find the number.

Phantasy [73]

Answer:

x = -7

Step-by-step explanation:

Eleven more than five times a number is equal to the difference between −38 and twice the number.

let x represent the number.

11 + 5x = -38 - 2x

7x +11 = -38.............add 2x to both sides

7x = -49................... subtract 11 from both sides

x = -7........................divide both sides by 7

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3 years ago

Help please please please

Juliette [100K]

Step-by-step explanation:

I don't know the area of the glass front of your largest building.

but just think :

1 gallon of fluid costs $12

1 gallon cleans 5000 ft²

so, now, find the area (ft²) of that glass front and see what number you have to multiply 5000 with to get the area of the glass front.

then, you have to multiply $12 with that same number, and you get the price.

let's say the building's glass front has 10000 ft².

what do I have to multiply with 5000 to get 10000 ?

this is the same question as how often fits 5000 into 10000 ? which is 10000 / 5000 = 2

and 12×2 = $24 as total cost to clean it.

our the building's glad front has 2500 ft².

what do I have to multiply with 5000 to get 2500 ?

this is the same question as how often fits 5000 into 2500 ? which is 2500 / 5000 = 1/2

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8 0

3 years ago

Shelby is an entrepreneur who has decided to open a small advertising firm. She rents office space at a cost of $25,000 per year

mestny [16]

Answer:

$ 125,000

Step-by-step explanation:

Given,

The amount of rent = $ 25,000,

The salary of assistant = $ 30, 000

Expenses = $ 20,000,

Also, her best alternative is to work elsewhere and to earn a salary of $50,000 per year.

Thus, the investment in the firm = 25000 + 30000 + 20000 + 50000

= $ 125,000,

Now, if she earns zero economic profit,

Then her revenue = investment

= $ 125,000

7 0

3 years ago

Read 2 more answers

◕ A dealer sold a photocopy machine at Rs 4200 with 13% VAT to a retailer. The retailer added transportation cost of Rs 250 , pr

satela [25.4K]

Given :-

A dealer sold a photocopy machine at Rs 4200 with 13% VAT to a retailer.
The retailer added transportation cost of Rs 250 , profit Rs 300 and local tax Rs 150 and sold to consumer .
Customer has to pay 13% VAT .

To Find :-

Amount to be paid by the customer .

Solution :-

Here , according to the question ,

$\sf\dashrightarrow Cost\ of \ machine \ = \ Rs 4200$

$\sf\dashrightarrow VAT = 13\%$

Therefore cost after adding VAT ,

$\sf\dashrightarrow Cost = Cost_{initial}+13\% of Cost_{initial}\\$

$\sf\dashrightarrow Cost = Rs4200 + Rs 4200 \times \dfrac{13}{100}\\$

$\sf\dashrightarrow Cost = Rs4200 + Rs546\\$

$\sf\dashrightarrow \bf{ Cost = Rs 4746}$

Again the values added by the retailer before selling to customer ,

Transport = Rs 250
Profit = Rs 300
Tax = Rs 150

Therefore total cost after adding these ,

$\sf\dashrightarrow Cost = Rs( 4746+ 250+ 300 + 150 )\\$

$\sf\dashrightarrow\bf { Cost = Rs 5446}$

Again Selling price after addition of 13% VAT ,

$\sf\dashrightarrow SP = Rs 5446 + 13\% \ of \ Rs 5446\\$

$\sf\dashrightarrow SP = Rs 5446 + \dfrac{13}{100}\times 5446 \\$

$\sf\dashrightarrow SP = Rs (5446 + 707.98) = Rs ( 5446 + 708)\\$

$\sf\dashrightarrow \underline{\underline{\bf SP_{to\ the \ customer} = Rs 6154}}$

Hence the amount to be paid by the customer is Rs 6154 .

3 0

2 years ago

Read 2 more answers