All categories

3 years ago

Solve the equation. 2(3z-2)+8=34 A. z=3 B. z=-3 C. z=-4 D. z=5

Mathematics

2 answers:

levacccp [35]3 years ago

6 0

<span>2(3z-2)+8=34
6z - 4 + 8 = 34
6z + 4 = 34
6z = 34 -4
6z = 30
z =30/6
z = 5

answer </span><span>D. z=5</span>

mario62 [17]3 years ago

4 0

<span>Step 1: 2(3z-2)+8=34
Step 2: 6z - 4 + 8 = 34
Step 3: 6z + 4 = 34
Step 4: 6z = 34 -4
Step 5: 6z = 30
Step 6: z =30/6
Step 7: z = 5

D is your answer : )
</span>

You might be interested in

A bag of marbles comes with 3 blue marbles, 2 red marbles, and 5 yellow marbles. What is the ratio of red to yellow?

FinnZ [79.3K]

Answer:2:5

Step-by-step explanation: you have 2 red marbles which is the numerator and 5 as the denominator because it is the bigger number .

8 0

3 years ago

What is the measure of b?

jolli1 [7]

Answer:

16.5

Step-by-step explanation:

8 0

2 years ago

What’s 7x (5-98) ^4 = x +2?

zvonat [6]

Answer:

<h3>YOUR ANSWER IS IN THE ATTACHMENT!! </h3>

<h2>HOPE IT HELPS U!!!! </h2>

4 0

2 years ago

Read 2 more answers

What fraction of a cup of vegetable oil should julia use to make 1\2 of a batch of salad dressing

anastassius [24]

A) 3/8. You cut 3/4 in half by making the bottom number twice as big and get 3/8

5 0

3 years ago

Read 2 more answers

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

2 years ago