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3 years ago

What is the solution to the system of equations?

Mathematics

1 answer:

sukhopar [10]3 years ago

8 0

Answer:

(x, y) = (-3, -6)

Step-by-step explanation:

The second equation can be used to write an expression for y:

... -5x -21 = y . . . . . . . add y-21 to both sides

This expression can be substituted for y in the first equation:

... 6 = -4x +(-5x -21)

... 27 = -9x . . . . . add 21, collect terms

... -3 = x . . . . . . . divide by -9

Using this value of x in the expression for y, we find ...

... -5(-3) -21 = y = -6

The solution is x = -3, y = -6.

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Use a graphing calculator to determine the linear, quadratic, or exponential equation that best represents the data. For linear

Sav [38]

The linear equation that best represents the data is given by:

y = 1.35x - 2.11.

<h3>Why is the data best represented by a linear equation?</h3>

We have to consider two things:

The data increases over the entire interval, not having changes in the behavior related to increasing/decreasing, hence a quadratic equation would not be a good representation for the data.

The increase is best followed by a constant, especially for higher values, and not by a multiplier, hence a linear function is selected over an exponential function.

<h3>How to find the equation of linear regression using a calculator?</h3>

To find the equation, we need to insert the points (x,y) in the calculator.

For this problem, the points are given as follows:

(1, 0.2), (2, 0.4), (3, 1.1), (4, 2.3), (5, 5.1), (6, 6.3), (7, 7.5).

Inserting these points into the calculator, the equation is given by:

y = 1.35x - 2.11.

More can be learned about linear equations at brainly.com/question/24808124

#SPJ1

3 0

1 year ago

A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized below

jok3333 [9.3K]

Answer:

The value of the test statistic = 2.58

Test statistic Z = - 4.805

|Z| = 4.805 > 2.58

Null hypothesis is rejected The value of the test statistic = 2.58

There is significant difference between in the mean number of times men and women send a Twitter message in a day

Step-by-step explanation:

Step(i):-

Sample size of men n₁ = 25

mean of the first sample x₁⁻ = 20

Standard deviation of the first sample σ₁ = 5

Sample size of women n₂ = 30

mean of the second sample x₂⁻ = 30

Standard deviation of the first sample σ₂ = 10

Level of significance ∝= 0.01

<u>Step(ii)</u>:-

Null Hypothesis : H₀: There is no significant difference between in the mean number of times men and women send a Twitter message in a day

Alternative Hypothesis :H₁:There is significant difference between in the mean number of times men and women send a Twitter message in a day

Test statistic

$Z = \frac{x^{-} _{1} - x^{-} _{2} }{\sqrt{\frac{S.D_{1} ^{2} }{n_{1} }+\frac{ S.D_{2} ^{2}}{n_{2} } } }$

$Z = \frac{20 - 30 }{\sqrt{\frac{(5)^{2} }{25 }+\frac{ (10)^{2} }{ 30} } }$

Z = $\frac{-10}{2.081} = - 4.805$

The value of the test statistic = 2.58 C

|Z| = 4.805 > 2.58

Null hypothesis is rejected The value of the test statistic = 2.58

<u>Conclusion:</u>-

There is significant difference between in the mean number of times men and women send a Twitter message in a day

7 0

3 years ago

Giving out 60 points

Yuki888 [10]

If the markers are 4.5 inches away on the map, and 2.5 inches represents 10 miles, then we need to make ratios we can work with.

Inches / Miles:

4.5 / x
2.5 / 10

Now, we can cross multiply to end up with:

2.5 * x = 4.5 * 10

Simplify:

2.5x = 45

Divide 2.5 on each side:

2.5x / 2.5 = 45 / 2.5

Simplify:

x = 45 / 2.5
x = 18

Awesome! Now we have a real ratio on the real distance of the markers.

<span>2.5 : 10 & 4.5 : </span><span>18.
</span>
18 miles is the actual distance between the two markers.

Hope I could help! If my math is wrong, or it isn't the answer you are looking for, please let me know!
<span>Have a good one!</span>

6 0

3 years ago

Which of the following ordered pairs is a solution of the given system of linear equations?

Over [174]

B. I'm terrible at explaining but I'm sure that's right.

4 0

3 years ago

Answer urgent please!!

butalik [34]

Answer:

Step-by-step explanation:

$u=5i-j\\\\v=3i+j\\\\w=i+4j\\$