All categories

3 years ago

Please help me with this.

Mathematics

1 answer:

inna [77]3 years ago

3 0

Answer:

Plot and connect (5,4), (3,0) and (7,0).

Step-by-step explanation:

This is in factored form and can be graphed directly from the equation. The equation shows the x-intercepts.

The x-intercepts are found by solving for x using the zero product rule.

(x-3)=0 so x = 3

(x-7) = 0 so x = 7

The intercepts are (3,0) and (7,0). Plot the points. The vertex will occur halfway between these points. 7-3 / 2 = 4/2 = 2. This means the axis of symmetry is at x = 5 and this is the x-coordinate of the vertex too.

Substitute x = 5 into the equation and solve for y.

-(5-3)(5-7) = -(2)(-2) = 4

The vertex is (5,4). Plot it and connect the points.

You might be interested in

A coach is assessing the correlation between the number of hours spent practicing and the average number of points scored in a g

cricket20 [7]

Answer:

a) $r=\frac{9(396)-(18)(153)}{\sqrt{[9(51) -(18)^2][9(3141) -(153)^2]}}=1$

We have a perfect linear relationship between the two variables

b) $m=\frac{90}{15}=6$

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

$\bar x= \frac{\sum x_i}{n}=\frac{18}{9}=2$

$\bar y= \frac{\sum y_i}{n}=\frac{153}{9}=17$

And we can find the intercept using this:

$b=\bar y -m \bar x=17-(6*2)=5$

So the line would be given by:

$y=6 x +5$

c) For this case the slope indicates that for each increase of the number of hours in 1 unit we have an expected increase in the score about 6 units.

And the intercept 5 represent the minimum score expected for any game

Step-by-step explanation:

We have the following data:

Number of hours spent practicing (x) 0 0.5 1 1.5 2 2.5 3 3.5 4

Score in the game (y) 5 8 11 14 17 20 23 26 29

Part a

The correlation coefficient is given:

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

For our case we have this:

n=9 $\sum x = 18, \sum y = 153, \sum xy = 396, \sum x^2 =51, \sum y^2 =3141$

$r=\frac{9(396)-(18)(153)}{\sqrt{[9(51) -(18)^2][9(3141) -(153)^2]}}=1$

We have a perfect linear relationship between the two variables

Part b

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

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:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=51-\frac{18^2}{9}=15$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i){n}}=396-\frac{18*153}{9}=90$

And the slope would be:

$m=\frac{90}{15}=6$

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

$\bar x= \frac{\sum x_i}{n}=\frac{18}{9}=2$

$\bar y= \frac{\sum y_i}{n}=\frac{153}{9}=17$

And we can find the intercept using this:

$b=\bar y -m \bar x=17-(6*2)=5$

So the line would be given by:

$y=6 x +5$

Part c

For this case the slope indicates that for each increase of the number of hours in 1 unit we have an expected increase in the score about 6 units.

And the intercept 5 represent the minimum score expected for any game

5 0

3 years ago

हवा से भी तेज चलने वाला कौन है

nevsk [136]

Step-by-step explanation:

हवा से भी तेज चलने वाली रोशनी है।

light travels faster than air

3 0

3 years ago

What is the solution to this addition sentence? 3/4 + (-1/2) = _____

Vikki [24]

$\text{Remove parentheses}\\\frac{3}{4} - \frac{1}{2} \\\text{Simplify}\\\frac{1}{4} \checkmark$

6 0

3 years ago

Read 2 more answers

What is the value of a 3 - b 2 for a = 3 and b = ?

stellarik [79]

Answer:

a^3 - b^2 for a = 3 and b = 1/2

3^3 - (1/2)^2

= 27 - 1/4

= 26 3/4

Step-by-step explanation:

7 0

3 years ago

a box of crackers has a volume of 48 cubic inches. what is the volume of a similar box that is smaller by a scale factor of 2/3

earnstyle [38]

For this case what you need to know is that the original volume of the cookie box is:
V = (w) * (l) * (h)
Where,
w: width
l: long
h: height.
We have then:
V = (w) * (l) * (h) = 48 in ^ 3
The volume of a similar box is:
V = (w * (2/3)) * (l * (2/3)) * (h * (2/3))
We rewrite:
V = ((w) * (l) * (h)) * ((2/3) * (2/3) * (2/3))
V = (w) * (l) * (h) * ((2/3) ^ 3)
V = 48 * ((2/3) ^ 3)
V = 14.22222222 in ^ 3
Answer:
the volume of a similar box that is smaller by a scale factor of 2/3 is:
V = 14.22222222 in ^ 3

6 0

3 years ago