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3 years ago

5x-4y=19 x-2y=8 Can someone please help me :))) Tenkss x

Mathematics

2 answers:

agasfer [191]3 years ago

8 0

Answer:

x=1/3

Step-by-step explanation:

5x-4y=19

2(2x-4y)=(9)2

____________

3x=1

x=1/3

I feel like i did this wrong

stira [4]3 years ago

6 0

Multiply the second row by 5

5x - 4y = 19

5x - 10y = 40

Subtract the 2nd row from the 1st row

6y = -21

Solve for y in the above equation

y = -7/2

Substitute y = -7/2 into any of the above equations. Let's pick the first one; 5x - 4y = 19

5x - 4 × -7/2 = 19

Solve for x in the equation above

x = 1

Therefore,

x = 1

y = -7/2

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Please help math question !! need range and domain for each picture thank you so much !

Lera25 [3.4K]

Answer: The correct option for figure 1 is (a) and correct option for figure 2 is (b).

Explanation:

Domain is the set of input and range is the set of output.

If a function is defined by f(x), then all the possible values of x is called domain and all the values of f(x) is called range.

In the figure (1) the elements of first set is input(Domain) and the elements of second set is output(Range).

The values of first set are -2,-1,0 and 2, so,

Domain = { -2, -1, 0, 2}

The values of second are -4, -2 and 2, so,

Range = { -4, -2, 2}

In figure (2) the values of x and y are given, the values of x are domain and the values of y are range.

The values of x are -4, -2, 1 and 4, so,

Domain = { -4, -2, 1, 4}

The values of y are -2, 1, 4 and 4,, Since the repetition of elements are not allowed in the set so,

Range = { -2, 1, 4}

Therefore, the option (a) is correct for figure (1) and the option (b) is correct for figure (2).

4 0

3 years ago

44. Melissa helps her grandfather at his store. Each mornin

Goryan [66]

<h2>HOW TO: SOLVE AN APPLICATION</h2>

Step 1. Identify what you are asked to find and choose a variable to represent it.

Step 2. Write a sentence that gives the information to find it.

Step 3. Translate the sentence into an equation.

Step 4. Solve the equation using good algebra techniques.

Step 5. Check the answer in the problem and make sure it makes sense.

Step 6. Write a complete sentence that answers the question.

Remember that whatever the application, once we write the sentence with the given information (Step 2), we can translate it to a percent equation and then solve it.

Do you pay a tax when you shop in your city or state? In many parts of the United States, sales tax is added to the purchase price of an item. See Figure 6.7. The sales tax is determined by computing a percent of the purchase price.

To find the sales tax multiply the purchase price by the sales tax rate. Remember to convert the sales tax rate from a percent to a decimal number. Once the sales tax is calculated, it is added to the purchase price. The result is the total cost—this is what the customer pays.

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3 years ago

Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail inste

Vladimir [108]

Answer:

The value of t test statistics is 5.9028.

We conclude that the true mean is greater than 10 at the .01 level of significance.

Step-by-step explanation:

We are given that a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead.

The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard deviation of 4.45 pages.

Let $\mu$ = true mean transmission of pages.

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Alternate Hypothesis, $H_A$ : $\mu$ > 10 pages {means that the true mean is greater than 10}

The test statistics that would be used here One-sample t test statistics as we don't know about the population standard deviation;

T.S. = $\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }$ ~ $t_n_-_1$

where, $\bar X$ = sample mean = 14.44 pages

s = sample standard deviation = 4.45 pages

n = sample of fax transmissions = 35

So, test statistics = $\frac{14.44-10}{\frac{4.45}{\sqrt{35} } }$ ~ $t_3_4$

= 5.9028

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Since our test statistics is more than the critical values of z as 5.9028 > 2.441, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.

Therefore, we conclude that the true mean is greater than 10.

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7 0

3 years ago

If I bought shoes for 32.30 with 15% off 7%sales tax a 25dollar gift card but had a coupon that was forgotten for 5%off the orig

Otrada [13]

Answer:

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Step-by-step explanation:

The discount was ...

0.15 × $32.30 = $4.845 ≈ $4.85

So the price to which tax is added is ...

$32.30 -4.85 = $27.45

The amount of tax is 7% of this value, or ...

tax = $27.45 × 0.07 = $1.9215 ≈ $1.92

So, payment is made on the amount ...

$27.45 + 1.92 = $29.37

$29.37 is the total amount paid.

If $25 is paid using a gift card, then the cash outlay is $4.37.

_____

Usually only a single coupon can be applied to a given purchase. Since the 15% store discount exceeds the amount of the 5% coupon left at home, it makes more sense to claim the 15% store discount and save the 5% coupon for another time.

Alternate interpretation

If, by some magic, both discounts could be applied, then the amount to be paid is $27.65, of which $2.65 exceeds the gift card amount. The calculation proceeds the same way, except that 20% is used instead of 15%.

4 0

3 years ago

To the nearest hundredth of a yard, determine the circumference of the given circle. Approximate as 3.14. r=6

Bond [772]

Answer:

37.68

Step-by-step explanation:

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7 0

3 years ago