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
Nady [450]
3 years ago
5

which linear system has been correctly solved for one of the variables from the following system? 2x - y = -1 2x y = -7 2x - y =

-1 y = 2x - 7 2x - y = -1 y = -2x 7 y = 2x 1 2x y = -7 y = -2x 7 2x y = -7
Mathematics
1 answer:
mr Goodwill [35]3 years ago
4 0
If you would like to solve the system of linear equations, you can do this using the following steps:

2x - y = -1 ... y = 2x + 1
2x + y = -7 ... y = -7 - 2x

The correct result would be: y = 2x + 1, <span>2x + y = -7.</span>
You might be interested in
The functions (x) and g(x) are defined below.
harina [27]
The answer is: A

I hope it’s helps you :)
6 0
3 years ago
A jump rope is 9 ft long . how long is the jump rope in yards
pav-90 [236]
The rope would be 3 yards long because every 3 feet is equal to 1 yard
7 0
3 years ago
Read 2 more answers
How do you get the answer 1 and 1/4-3/8
JulijaS [17]
U first find the common denominator which is 8

Then subtract to get 7/8

5 0
3 years ago
The results of a common standardized test used in psychology research is designed so that the population mean is 145 and the sta
anygoal [31]

The value 155 is zero standard deviations from the mean, because x = μ , and therefore z = 0.

<h3>What is Standard Deviation?</h3>

The standard deviation is a measure of the amount of variation or dispersion of a set of values.

The key concept we need to manage here is the z-scores , and we can obtain a z-score using the next formula:

z = (x - μ)/σ      ..............[1]

Where

z is the z-score.

x is the raw score: an observation from the normally distributed data that we want standardize using [1].

μ is the population mean.

σ is the population standard deviation.

These standardized values have always the same probability in the standard normal distribution, and this is the advantage of using it for calculating probabilities for normally distributed data.

A subject earns a score of 155.

From the question, we know that:

x = 155.

μ = 155

σ = 50

Having into account all the previous information, we can say that the raw score, x = 155, is zero standard deviations units from the mean. The subject earned a score that equals the population mean. Then, using [1]:

z = (x - μ)/σ

z = (155 - 155) / 50

z = 0/50

z = 0

As we say before, the z-score "tells us" the distance from the population mean, and in this case this value equals zero:  

x = μ

Therefore, z = 0

So, the value 155 is zero standard deviations from the [population] mean.

Learn more about Standard Deviation from:

brainly.com/question/13905583

#SPJ1

8 0
2 years ago
Evaluate the following
IRINA_888 [86]

(a) [\frac{9}{2.6}  - \frac{2.5^{2} }{2.5} ]^{2}

Answer:

[\frac{9}{2.6}  - \frac{2.5^{2} }{2.5} ]^{2}

= [\frac{9}{2.6}  - \frac{2.5*2.5 }{2.5} ]^{2}

= [\frac{9}{2.6}  - \frac{2.5}{1} ]^{2}

*canceling 2.5 in numerator and denominator*

= [\frac{9-(2.5)(2.6)}{2.6} ]^2\\*Using L.C.M of 2.6 and 1 which comes out to be '2.6'= [\frac{9-(6.5)}{2.6} ]^2\\= [\frac{2.5}{2.6} ]^2\\*multiplying and dividing by '10'= [\frac{2.5*10}{2.6*10} ]^2\\= [\frac{25}{26} ]^2\\= \frac{25^2}{26^2}\\= \frac{625}{676}\\= 0.925

Properties used:

Cancellation property of fractions

Least Common Multiplier(LCM)

The least or smallest common multiple of any two or more given natural numbers are termed as LCM. For example, LCM of 10, 15, and 20 is 60.

(b) [[\frac{3x^{a}y^{b}} {-3x^{a} y^{b} } ]^{3}    ] ^{2}

Answer:

[[\frac{3x^{a}y^{b}} {-3x^{a} y^{b} } ]^{3}] ^{2}\\

*using [x^{a}]^b = x^{ab}*

= [\frac{3x^{3a}y^{3b}} {-3x^{3a} y^{3b} }] ^{2}        

*Again, using [x^{a}]^b = x^{ab}*

= \frac{3x^{2*3a}y^{2*3b}} {-3x^{2*3a} y^{2*3b} }  \\= (-1)\frac{3x^{6a}y^{6b}} {3x^{6a} y^{6b} }\\[\tex]*taking -1 common, denominator and numerator are equal*[tex]= -(1)\frac{1}{1}\\= -1

Property used: 'Power of a power'

We can raise a power to a power

(x^2)4=(x⋅x)⋅(x⋅x)⋅(x⋅x)⋅(x⋅x)=x^8

This is called the power of a power property and says that to find a power of a power you just have to multiply the exponents.

3 0
3 years ago
Other questions:
  • If a laptop originally costs $800, the balance due after the 10% discount and $150 gift card is applied is $
    9·2 answers
  • If f(x) = 2x + 1 and g(x) = x^2 find g(f(3))<br> 49<br> 19<br> 7<br> 13
    13·1 answer
  • 1/4s - 4 - 2/3s = 5<br><br> what is the value of s
    7·2 answers
  • Please answer this correctly I have to finish the sums by today
    7·2 answers
  • The correlation analysis assumes that the measurements have a bivariate normal distribution in the population. Select all of the
    15·1 answer
  • Bailey earned $210 last month. She
    14·1 answer
  • Find the value of the following​
    7·1 answer
  • What is 10x -5 + 3x -2
    13·1 answer
  • Y plus 4 plus 3(y plus 2)
    14·2 answers
  • At a graduation dinner there were 47 guests in all. An equal number of guests were seated at each of 7 large​ tables, and 5 ​lat
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!