Whats equevalent to 3/8

Identify the zero(s) of <img src="https://tex.z-dn.net/?f=f%28x%29%3D4x%5E%7B2%7D%20-%2020x%20-%2056" id="TexFormula1" title="f(

AURORKA [14]

Answer:

x = - 2, x = 7

Step-by-step explanation:

Given

f(x) = 4x² - 20x - 56

To find the zeros let f(x) = 0, that is

4x² - 20x - 56 = 0 ( divide through by 4 )

x² - 5x - 14 = 0 ← in standard form

(x - 7)(x + 2) = 0 ← in factored form

Equate each factor to zero and solve for x

x + 2 = 0 ⇒ x = - 2

x - 7 = 0 ⇒ x = 7

5 0

2 years ago

An automobile dealer wants to see if there is a relationship between monthly sales and the interest rate. A random sample of 4 m

SVETLANKA909090 [29]

Answer:

a) $y=-6.254 x +75.064$

b) r =-0.932

The % of variation is given by the determination coefficient given by $r^2$ and on this case $-0.932^2 =0.8687$ , so then the % of variation explained by the linear model is 86.87%.

Step-by-step explanation:

Assuming the following dataset:

Monthly Sales (Y) Interest Rate (X)

22 9.2

20 7.6

10 10.4

45 5.3

Part a

And we want a linear model on this way y=mx+b, where m represent the slope and b the intercept. In order to find the slope we have this formula:

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

Where:

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

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

With these we can find the sums:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=278.65-\frac{32.5^2}{4}=14.5875$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i){n}}=696.9-\frac{32.5*97}{4}=-91.225$

And the slope would be:

$m=\frac{-91.225}{14.5875}=-6.254$

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

$\bar x= \frac{\sum x_i}{n}=\frac{32.5}{4}=8.125$

$\bar y= \frac{\sum y_i}{n}=\frac{97}{4}=24.25$

And we can find the intercept using this:

$b=\bar y -m \bar x=24.25-(-6.254*8.125)=75.064$

So the line would be given by:

$y=-6.254 x +75.064$

Part b

For this case we need to calculate the correlation coefficient given by:

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

$r=\frac{4(696.9)-(32.5)(97)}{\sqrt{[4(278.65) -(32.5)^2][4(3009) -(97)^2]}}=-0.937$

So then the correlation coefficient would be r =-0.932

The % of variation is given by the determination coefficient given by $r^2$ and on this case $-0.932^2 =0.8687$ , so then the % of variation explained by the linear model is 86.87%.

6 0

3 years ago

What is the domain of the relation {(0,1),(2,4),(3,7),(5,4)}

Zina [86]

Answer:

(0 2,3,5)

Step-by-step explanation:

Domain is the x factor of every relation

7 0

3 years ago

Is the circle inside the hexagon or hexagon inside the circle?

nexus9112 [7]

It could be either, we need more info. How big are each? If it doesn't say, then it's a trick question. Throw Schrodinger's cat at it or something.

8 0

3 years ago

Lee is staying at a hotel. The cost of the first night is $240. The cost for each night after that is $210. Let y represent the

GenaCL600 [577]

A) The situation represents an arithmetic sequence because the successive y-values have a common difference of 210.

F(1) = 240 +210

F(2) = 240 +2(210)

F(3) = 240+3(210)

.

F(x)= 240 +210x.

Learn more about Sequence:

brainly.com/question/12246947

#SPJ4

3 0

2 years ago