1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ch4aika [34]
3 years ago
15

Solve the system by substitution.

Mathematics
1 answer:
Butoxors [25]3 years ago
4 0

<u>Answer:</u>

The solution set of given equations -x-y-z = -8 and - 4x + 4y + 5z = 7 and 2x + 2z = 4  is (3, 6, -1)

<u>Solution:</u>

Given, set linear equations are

-x – y – z = -8 ⇒ x + y + z = 8 → (1)

-4x + 4y + 5z = 7 ⇒ 4x – 4y – 5z = -7 → (2)

2x + 2z = 4 ⇒ x + z = 2 → (3)

We have to solve the above given equations using substitution method.

Now take (3), x + z = 2 ⇒ x = 2 – z  

So substitute x value in (1)  

(1) ⇒ (2 – z) + y + z = 8 ⇒ 2 + y + z – z = 8 ⇒ y + 0 = 8 – 2 ⇒ y = 6.

Now substitute x and y values in (2)

(2) ⇒ 4(2 – z) – 4(6) – 5z = - 7 ⇒ 8 – 4z – 24 – 5z = -7 ⇒ -9z – 16 = -7 ⇒ 9z = 7 – 16 ⇒ 9z = -9 ⇒ z = -1

Now substitute z value in (3)

(3) ⇒ x – 1 = 2 ⇒ x = 2 + 1 ⇒ x = 3

Hence, the solution set of given equations is (3, 6, -1).

You might be interested in
Pip was thinking of a number subtracts 13 and gets answer of 30.3 what was original number
olasank [31]

Answer:

393.9

Step-by-step explanation:

Multiply 30.3 with 13.. Will get the answer 393.9

30.3= x / 13

X = 30.3 x 13

5 0
3 years ago
Read 2 more answers
What’s the answer to this math problem?v
Ann [662]
It’s A or D but I have a strong feelin it’s A
7 0
3 years ago
Read 2 more answers
Write four solution of the equation=2x+y=7​
Fantom [35]

Step-by-step explanation:

x = 1, y = 5

x = 2, y = 3

x =3, y= 1

x=4 y=-1

4 0
3 years ago
in a program designed to help patients stop smoking 232 patients were given sustained care and 84.9% of them were no longer smok
grandymaker [24]

Answer:

z=\frac{0.849 -0.8}{\sqrt{\frac{0.8(1-0.8)}{232}}}=1.869  

p_v =2*P(Z>1.869)=0.0616  

If we compare the p value obtained and the significance level given \alpha=0.05 we see that p_v>\alpha so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of adults were no longer smoking after one month is not significantly different from 0.8 or 80% .  

Step-by-step explanation:

1) Data given and notation

n=232 represent the random sample taken

X represent the adults were no longer smoking after one month

\hat p=0.849 estimated proportion of adults were no longer smoking after one month

p_o=0.80 is the value that we want to test

\alpha=0.05 represent the significance level

Confidence=95% or 0.95

z would represent the statistic (variable of interest)

p_v represent the p value (variable of interest)  

2) Concepts and formulas to use  

We need to conduct a hypothesis in order to test the claim that the true proportion is 0.8.:  

Null hypothesis:p=0.8  

Alternative hypothesis:p \neq 0.8  

When we conduct a proportion test we need to use the z statistic, and the is given by:  

z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}} (1)  

The One-Sample Proportion Test is used to assess whether a population proportion \hat p is significantly different from a hypothesized value p_o.

3) Calculate the statistic  

Since we have all the info requires we can replace in formula (1) like this:  

z=\frac{0.849 -0.8}{\sqrt{\frac{0.8(1-0.8)}{232}}}=1.869  

4) Statistical decision  

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.  

The significance level provided \alpha=0.05. The next step would be calculate the p value for this test.  

Since is a bilateral test the p value would be:  

p_v =2*P(Z>1.869)=0.0616  

If we compare the p value obtained and the significance level given \alpha=0.05 we see that p_v>\alpha so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of adults were no longer smoking after one month is not significantly different from 0.8 or 80% .  

6 0
3 years ago
If 2×2=4 and 4×4=8. What is 8×8?​
Oxana [17]

Answer:

64

Step-by-step explanation:

7 0
3 years ago
Read 2 more answers
Other questions:
  • the graph shows rate at which an oven preheats when turned on. what is the unit rate and what does it represent?
    8·2 answers
  • What are the coordinates of the point that divides AB in the ratio 2:3?
    5·1 answer
  • -7(x+7=-56 I really need help
    9·1 answer
  • What is the greatest common factor GCF GCF of 12 and 18
    9·2 answers
  • Suppose you read 1000 pages a month. How long would take you to finish reading 1million pages? ​
    5·1 answer
  • What is the slope of (-13,8) and (3,12)
    10·1 answer
  • 6 ten thousands mutilply 10 = what
    14·1 answer
  • Christmas present shhh:)
    15·1 answer
  • Gold’s gym charges $30 membership fee plus $3 for each workout, while Titletown charges $40 membership fee plus $1 for each work
    7·1 answer
  • Which of these systems of linear equations has an infinite number of solution
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!