All categories

3 years ago

X - y = 3 x + 3y = 9

2 answers:

7 0

Solve for one of the variables in the first equation (in this case, I will solve for X):
X = Y + 3

Then use that value of X in the second equation to solve for Y:
X + 3Y = 9
(Y + 3) + 3Y = 9
4Y + 3 = 9
4Y = 6
Y = 1.5

Use the value of Y we just found in the X equation we created:
X = Y + 3
X = 1.5 + 3
X = 4.5

Therefore X = 4.5 or 9/2 and Y = 1.5 or 3/2.

Verizon [17]3 years ago

3 0

X - y = 3 is the same as x=3+y 

3+y+3y = 9 

3+4y=9 

4y=9-3

4y=6

y=6/4

y=3/2 

x-(3/2)=3 

x=3+(3/2) 

x=6/2+3/2 


x=9/2

You might be interested in

camelback mountain has an elevation change of 1,264 feet. how many pennies would it take to make a stack that high ? show all wo

gtnhenbr [62]

Camel back Mountain = 15,168 inches (1,264 feet)

1 Penny = 0.061 (.0610) Inches

10 Penny = 0.61 (.610) Inches

100 Penny = 6.1 (6.10) Inches

1,000 Penny = 61 (61.0) Inches

10,000 Penny = 610 (610.0) Inches

-SOLVING-

10,000 Penny = 610 inches PLUS

1,000 Penny = 61 inches AND 61 inches x 5 = 305 (5,000 Penny)

100 Penny = 6.1 inches PLUS

10 Penny = 0.61 inches AND 0.61 inches x 6 = 3.66 (60 Penny)

1 Penny = 0.061 inches AND 0.061 inches x 8 = 0.488 (8 Penny)

-FINAL ANSWER-

610 + 305 + 6.1 + 3.66 + 0.488 = 925.248 Penny it would take.

3 0

2 years ago

The following results come from two independent random samples taken of two populations.

photoshop1234 [79]

Answer:

$(a)\ \bar x_1 - \bar x_2 = 2.0$

$(b)\ CI =(1.0542,2.9458)$

$(c)\ CI = (0.8730,2.1270)$

Step-by-step explanation:

Given

$n_1 = 60$ $n_2 = 35$

$\bar x_1 = 13.6$ $\bar x_2 = 11.6$

$\sigma_1 = 2.1$ $\sigma_2 = 3$

Solving (a): Point estimate of difference of mean

This is calculated as: $\bar x_1 - \bar x_2$

$\bar x_1 - \bar x_2 = 13.6 - 11.6$

$\bar x_1 - \bar x_2 = 2.0$

Solving (b): 90% confidence interval

We have:

$c = 90\%$

$c = 0.90$

Confidence level is: $1 - \alpha$

$1 - \alpha = c$

$1 - \alpha = 0.90$

$\alpha = 0.10$

Calculate $z_{\alpha/2}$

$z_{\alpha/2} = z_{0.10/2}$

$z_{\alpha/2} = z_{0.05}$

The z score is:

$z_{\alpha/2} = z_{0.05} =1.645$

The endpoints of the confidence level is:

$(\bar x_1 - \bar x_2) \± z_{\alpha/2} * \sqrt{\frac{\sigma_1^2}{n_1}+\frac{\sigma_2^2}{n_2}}$

$2.0 \± 1.645 * \sqrt{\frac{2.1^2}{60}+\frac{3^2}{35}}$

$2.0 \± 1.645 * \sqrt{\frac{4.41}{60}+\frac{9}{35}}$

$2.0 \± 1.645 * \sqrt{0.0735+0.2571}$

$2.0 \± 1.645 * \sqrt{0.3306}$

$2.0 \± 0.9458$

Split

$(2.0 - 0.9458) \to (2.0 + 0.9458)$

$(1.0542) \to (2.9458)$

Hence, the 90% confidence interval is:

$CI =(1.0542,2.9458)$

Solving (c): 95% confidence interval

We have:

$c = 95\%$

$c = 0.95$

Confidence level is: $1 - \alpha$

$1 - \alpha = c$

$1 - \alpha = 0.95$

$\alpha = 0.05$

Calculate $z_{\alpha/2}$

$z_{\alpha/2} = z_{0.05/2}$

$z_{\alpha/2} = z_{0.025}$

The z score is:

$z_{\alpha/2} = z_{0.025} =1.96$

The endpoints of the confidence level is:

$(\bar x_1 - \bar x_2) \± z_{\alpha/2} * \sqrt{\frac{\sigma_1^2}{n_1}+\frac{\sigma_2^2}{n_2}}$

$2.0 \± 1.96 * \sqrt{\frac{2.1^2}{60}+\frac{3^2}{35}}$

$2.0 \± 1.96* \sqrt{\frac{4.41}{60}+\frac{9}{35}}$

$2.0 \± 1.96 * \sqrt{0.0735+0.2571}$

$2.0 \± 1.96* \sqrt{0.3306}$

$2.0 \± 1.1270$

Split

$(2.0 - 1.1270) \to (2.0 + 1.1270)$

$(0.8730) \to (2.1270)$

Hence, the 95% confidence interval is:

$CI = (0.8730,2.1270)$

8 0

3 years ago

A ) 4.05 per pound B) $5.40 per pound C) $2.70 per pound D) $1.35 per pound

Nadusha1986 [10]

Answer:

D is the correct answer

Step-by-step explanation:

As you see, the product of peaches 1 and 2 have the different in cost is $1.35 and $2.70. As well as the following product of peaches also have the same increase in money.

So 2.70 - 1.35 = 1.35 so the common increase would be $1.35

Hope this help you :3

6 0

2 years ago

The late fee for library books is $2.00 plus 15 cents each day for a book that is late.If Maria's fee for a late book was $3.20,

tekilochka [14]

First we will subtract $2 from $3.2 since that is late fee to get $1.2.

Now we divide $1.2 by $0.15 to get number of cents hence 8 days.

The answer is Maria is 8 days too late to hand over the book.

Hope this helps.

5 0

3 years ago

Helppppppppppppppppppp

Schach [20]

Answer:

1/8^4

Step-by-step explanation:

when divinding exponents with the same base, subtract the power. you get 8^-4. since the problem specifies no negative exponents you need to simplify. this give you 1/8^4

7 0

2 years ago