Ask question

Ask question

All categories

3 years ago

11

3y-5x=15 Please help me! How do I do this if there is any and an x???

1 answer:

TiliK225 [7]3 years ago

5 0

I think it 3y=3x I hope help you out

You might be interested in

____ [38]

The answer is quadrant 2

7 0

3 years ago

Read 2 more answers

14.7x + 4x = 0*(46y+39y) Y=14, Solve for X

Dovator [93]

14.7x + 4x = 0*(49y+39y) y = 14

18.7x = 0(686 + 546)

18.7x = 0

x = 0

4 0

3 years ago

Assume you have noted the following prices for books and the number of pages that each book contains. Book Pages (x) Price (y) A

belka [17]

Answer:

a) $y=0.00991 x +1.042$

b) $r^2 = 0.7503^2 = 0.563$

c) $r=\frac{7(30095)-(4210)(49)}{\sqrt{[7(2595100) -(4210)^2][7(354) -(49)^2]}}=0.7503$

Step-by-step explanation:

Data given

x: 500, 700, 750, 590 , 540, 650, 480

y: 7.00, 7.50 , 9.00, 6.5, 7.50 , 7.0, 4.50

Part a

We want to create a linear model like this :

$y = mx +b$

Wehre

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

And:

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

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

With these we can find the sums:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=2595100-\frac{4210^2}{7}=63085.714$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i){n}}=30095-\frac{4210*49}{7}=625$

And the slope would be:

$m=\frac{625}{63085.714}=0.00991$

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

$\bar x= \frac{\sum x_i}{n}=\frac{4210}{7}=601.429$

$\bar y= \frac{\sum y_i}{n}=\frac{49}{7}=7$

And we can find the intercept using this:

$b=\bar y -m \bar x=7-(0.00991*601.429)=1.042$

And the line would be:

$y=0.00991 x +1.042$

Part b

The correlation coefficient is given by:

$r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}$

For our case we have this:

n=7 $\sum x = 4210, \sum y = 49, \sum xy = 30095, \sum x^2 =2595100, \sum y^2 =354$

$r=\frac{7(30095)-(4210)(49)}{\sqrt{[7(2595100) -(4210)^2][7(354) -(49)^2]}}=0.7503$

The determination coefficient is given by:

$r^2 = 0.7503^2 = 0.563$

Part c

$r=\frac{7(30095)-(4210)(49)}{\sqrt{[7(2595100) -(4210)^2][7(354) -(49)^2]}}=0.7503$

4 0

3 years ago

Help me pls!!!!!!!!!

Dominik [7]

Answer:

$x^2+18=-9x : x = -3, x = -6$

Step-by-step explanation:

$x^2+18=-9x$

Add 9x to both sides:

$x^2+18+9x=-9x+9x$

Simplify:

$x^2+9x+18=0$

Solve with the quadratic formula:

For a quadratic equation of the form $ax^2+bx+c=0$ the solutions are:

$x_{1,\:2}=\frac{-b\pm \sqrt{b^2-4ac}}{2a}$

For $a=1,\:b=9,\:c=18:\quad x_{1,\:2}=\frac{-9\pm \sqrt{9^2-4\cdot \:1\cdot \:18}}{2\cdot \:1}$

$x =\frac{-9 + \sqrt{9^2-4\cdot \:1\cdot \:18}}{2\cdot \:1} : -3$

$x =\frac{-9 - \sqrt{9^2-4\cdot \:1\cdot \:18}}{2\cdot \:1} : -6$

The solution to the quadratic equation are:

$x=-3,\:x=-6$

Hope I helped. If so, may I get brainliest and a thanks?

Thank you, have a good day!

6 0

3 years ago

Let's investigate

AlexFokin [52]

You would need to leave the dentist at 2:40.

4 0

3 years ago