All categories

4 years ago

How do you solve this??????? 3x+6=-5-2x-6

Mathematics

1 answer:

Elina [12.6K]4 years ago

4 0

Answer:

Step-by-step explanation:

3x+6=-5-2x-6

+2x. +2x

5x+6= -5-6

5x+6= -11

-6. -6

5x= -17

divide by 5

x= -3.4

You might be interested in

Simplify: j + 5 + 5c

irina [24]

The answer is 5
c
+
j
+
5

5 0

3 years ago

Modern medical practice tells us not to encourage babies to become too fat. Is there a positive correlation between the weight x

Anna11 [10]

Answer:

a) Figure attached

b) $y=1.31 x +98.57$

c) The correlation coefficient would be r =0.47719

d) $y=1.31 x +98.57=1.31*21 + 98.57 =126.08$

Step-by-step explanation:

(a) Draw a scatter diagram for the data.

See the figure attached

(b) Find x, y, b, and the equation of the least-squares line. (Round your answers to three decimal places.) x =__ y =__ b =__ y =__ + __x

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

Where:

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

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

With these we can find the sums:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=6576-\frac{300^2}{14}=147.429$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i){n}}=38186-\frac{300*1773}{14}=193.143$

And the slope would be:

$m=\frac{193.143}{147.429}=1.31$

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

$\bar x= \frac{\sum x_i}{n}=\frac{300}{14}=21.429$

$\bar y= \frac{\sum y_i}{n}=\frac{1773}{14}=126.643$

And we can find the intercept using this:

$b=\bar y -m \bar x=126.643-(1.31*21.429)=98.571$

So the line would be given by:

$y=1.31 x +98.57$

(c) Find the sample correlation coefficient r and the coefficient of determination r?2. (Round your answers to three decimal places.)

n=14 $\sum x = 300, \sum y = 1773, \sum xy=38186, \sum x^2 =6576, \sum y^2 =225649$

And in order to calculate the correlation coefficient we can use this formula:

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

$r=\frac{14(38186)-(300)(1773)}{\sqrt{[14(6576) -(300)^2][14(225649) -(1773)^2]}}=0.9534$

So then the correlation coefficient would be r =0.47719

What percentage of variation in y is explained by the least-squares model? (Round your answer to one decimal place.)

The % of variation is given by the determination coefficient given by $r^2$ and on this case $0.47719^2 =0.2277$ , so then the % of variation explaines is 22.8%.

(d) If a female baby weighs 21 pounds at 1 year, what do you predict she will weigh at 30 years of age? (Round your answer to two decimal places.) ___ lb

So we can replace in the linear model like this:

$y=1.31 x +98.57=1.31*21 + 98.57 =126.08$

7 0

3 years ago

In a right triangle the length of a hypotenuse is c and the length of one leg is a, and the length of the other leg is b, what i

swat32

Apply the Pythagoras Theorem

${c }^{2} = {a}^{2} + {b}^{2}$
${9 }^{2} = {7}^{2} + {b}^{2}$
$81 = 49+ {b}^{2}$
$81 - 49 = {b}^{2}$
$32= {b}^{2}$
Take square root of both sides

$b = \sqrt{32}$
$b = 4 \sqrt{2}$

5 0

4 years ago

Read 2 more answers

Given f(x) = x and h(x) = f(x) - 3, how does h(x) compare to f(x)?

olga2289 [7]

Answer:

H(x) is less than f(xl

Step-by-step explanation:

Whether f(x)=3 or -4, h(x)'s value will always be less than f(x).

7 0

3 years ago

The 12th term and the sim of 1+3+5+7+.....

zzz [600]

To find this, first find the factor or rate of which the numbers are moving. To do so do as follows.

subtract 1 from 3

3-1=2

So each number is having 2 added to it.

Now add two to 7 and the numbers afterwards till you get the 12th term

7+2=9

1+3+5+7+9

9+2=11

1+3+5+7+9+11

11+2=13

1+3+5+7+9+11+13

13+2=15

1+3+5+7+9+11+13+15

15+2=17

1+3+5+7+9+11+13+15+17

17+2=19

1+3+5+7+9+11+13+15+17+19

19+2=21

1+3+5+7+9+11+13+15+17+19+21

21+2=23

1+3+5+7+9+11+13+15+17+19+21+23

So 23 is the 12th term

7 0

4 years ago