All categories

3 years ago

What is the solution to the system of linear equations?

Mathematics

1 answer:

Dmitry_Shevchenko [17]3 years ago

4 0

Answer:

x = 5, y = -1/2

Step-by-step explanation:

3.5x - 5y = 20

3x + 4y = 13 multiply by 1.25 so the y's match up (you could match x's too)

3.75x + 5y = 16.25

–––––––––––––––––––––––

3.5x - 5y = 20

3.75x +5y = 16.25

7.25x + 0y = 36.25 you can add or subtract here (on this equation you add)

7.25x=36.25

x=5 So now we have x=5 and to find y we can just plug in x into one of the equations

–––––––––––––––––––

3(5) + 4y = 13

15 + 4y = 13

4y = -2

y = -1/2

x = 5, y = -1/2

Then you can plug in both to check your answers.

You might be interested in

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

2 years ago

HELPPPPPPP ASAPPPPP PLEASEEE

Kobotan [32]

<h3>Answer: </h3><h3>See the attached image below for the table</h3>

In column 1 we have the x values 0, 4, 8, 12

In column 2, we have the y values 1, 2, 3, 4

==================================================

Explanation:

We can start with any x value we want. I find that 0 is easiest to work with, so why not start at x = 0. For the sake of not repeating, I'll use y = 1 as the start value for y.

The first row of the table is x = 0 and y = 1.

A slope of 1/4 means rise/run = 1/4. So rise = 1 and run = 4.

A rise of 1 indicates y goes up by 1. A run of 4 means x increases by 4.

So put together, slope = 1/4 means each time x goes up by 4, y goes up by 1.

-----------

If we started at x = 0, then going up by 4 leads to x = 4. If y starts at y = 1, then going up by 1 leads to y = 2.

The second row of the table is x = 4 and y = 2

We'll repeat the pattern of "add 4 to x, add 1 to y" getting the third row having x = 8 and y = 3

We can repeat as many times as we want. Doing another "up 1, over to the right 4" movement lands us on (x,y) = (12, 4)

The completed table is shown below in the attached image.

-----------

If you were to use the slope formula with any two rows of the table, then you should get m = 1/4

Let's do the first two rows

m = (y2-y1)/(x2-x1)

m = (2-1)/(4-0)

m = 1/4

I'll let you check the other pairs of rows.

3 0

3 years ago

What is 1% of 3,000?

gladu [14]

Answer:

Step-by-step explanation:

As 1 percent is equal to 1/100

1/100 of 3000 (1/100 x 3000)

equals to...

3 0

2 years ago

Read 2 more answers

I need help please and ty 2 questions in math for a lot of points

Vlad1618 [11]

Answer: ok we will help

Step-by-step explanation:

he need our help

4 0

2 years ago

How many degrees is one rotation that will put a regular pentagon back on top of itself?

Dmitriy789 [7]

If you rotate about the circumcentre of a regular polygon 72° it will overlap with the original image.

8 0

3 years ago