All categories

3 years ago

2x - y=4 y=4 - 2x Give your answer as an ordered pair.

Mathematics

1 answer:

algol133 years ago

7 0

Answer:

Step-by-step explanation:

<h3>for the first question:-2x-4-2x=4</h3><h3>2x-2x=4+4</h3><h3>x=8</h3><h3>y=4-2x</h3><h3>y=4-2×8</h3><h3>y=12 </h3>

You might be interested in

Some types of algae have the potential to cause damage to river ecosystems. Suppose the accompanying data on algae colony densit

Phantasy [73]

Answer:

$y=-2.95836 x +234.56159$

Step-by-step explanation:

We assume that th data is this one:

x: 50, 55, 50, 79, 44, 37, 70, 45, 49

y: 152, 48, 22, 35, 43, 171, 13, 185, 25

a) Compute the equation of the least-squares regression line. (Round your numerical values to five decimal places.)For this case we need to calculate the slope with the following formula:

$m=\frac{S_{xy}}{S_{xx}}$

Where:

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}{n}$

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}$

So we can find the sums like this:

$\sum_{i=1}^n x_i =50+ 55+ 50+ 79+ 44+ 37+ 70+ 45+ 49=479$

$\sum_{i=1}^n y_i =152+ 48+ 22+ 35+ 43+ 171+ 13+ 185+ 25=694$

$\sum_{i=1}^n x^2_i =50^2 + 55^2 + 50^2 + 79^2 + 44^2 + 37^2 + 70^2 + 45^2 + 49^2=26897$

$\sum_{i=1}^n y^2_i =152^2 + 48^2 + 22^2 + 35^2 + 43^2 + 171^2 + 13^2 + 185^2 + 25^2=93226$

$\sum_{i=1}^n x_i y_i =50*152+ 55*48+ 50*22+ 79*35+ 44*43+ 37*171+ 70*13+ 45*185+ 49*25=32784$

With these we can find the sums:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=26897-\frac{479^2}{9}=1403.556$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}=32784-\frac{479*694}{9}=-4152.22$

And the slope would be:

$m=-\frac{-4152.222}{1403.556}=-2.95836$

Nowe we can find the means for x and y like this:

$\bar x= \frac{\sum x_i}{n}=\frac{479}{9}=53.222$

$\bar y= \frac{\sum y_i}{n}=\frac{694}{9}=77.111$

And we can find the intercept using this:

$b=\bar y -m \bar x=77.1111111-(-2.95836*53.22222222)=234.56159$

So the line would be given by:

$y=-2.95836 x +234.56159$

7 0

3 years ago

Help me and explain

yan [13]

TOTAL IS $10

If the party costs $5 and each additional person is $1 and she invites 5 more 5 X 1 = 5

OR 1 + 1 + 1 + 1 + 1

4 0

3 years ago

An equation is shown.

Anit [1.1K]

We take the equation 4x+y=5 and subtract 4x from both sides to get
y = 5 - 4x
The answer to this question is <span>y=5−4x.</span>

4 0

3 years ago

A member was charged 260$usd and then applied for financial aid and received a 30% discount . They reach out and ask for the 30%

sergiy2304 [10]

Answer:

The total charge with the discount is $182

The refund is $78

Step-by-step explanation:

Given data

Charge= $260

Discount=30%

Let us find the amount of the 30%

=30/100*260

=0.3*260

=$78

The new charge after the discount is

=260-78

=$182

The total charge with the discount is $182

The refund is $78

5 0

3 years ago

Help Will Mark Brainliest

Mashcka [7]

Question 1:

Choir A - 129.5 = 130

Choir B - 130.1 = 130

Choir C - 130.8 = 131

Choir D - 129.8 = 130

Answer - Choir C

Question 2:

132 = 1/2x + 2(x - 9)

= 1/2(60) + 2(60 - 9)

= 30 + 102

= 132

60 - 9 = 51

Answer - The cost of a children's ticket is $51

5 0

3 years ago