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2 years ago

Find the value of cos C rounded to the nearest hundredth, if necessary

Mathematics

1 answer:

Sindrei [870]2 years ago

6 0

$\bold{\frac{5}{13} or 0.38}$

Answer:

Solution given:

here

by using Pythagoras law

hypotenuse =

$\displaystyle\sqrt{adjacent ²+opposite ²}\\=\sqrt{15²+36²}=39$

Cos C= $\frac{adjacent} {hypotenuse}=\frac{15}{39}=\frac{5}{13} or{0.38}$

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Uhhh do i need to know whats 4+10

lara31 [8.8K]

Answer:

Step-by-step explanation:

see you take 10 objects and then add 4 more objects and count the result.

6 0

3 years ago

In the diagram shown, line m is parallel to line n . Justine says that ∠3 ∠ 3 and ∠7 ∠ 7 are supplementary angles. Is she correc

agasfer [191]

The correct answer is C.

Because by looking at the diagram you can see that angles 7 and 8 are intersected

6 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

The area of a circle A is 85π ft2. ∠BAC is a central angle of the circle, and m∠BAC = 36°

BlackZzzverrR [31]

As stated the area of the circle is 85π ft2. The area of the sector BAC is a portion of this full circle area. the sector is made of 2 radii and arc that has rotated by 36°.
the magnitude of the central angle in the circle is 360°
Area for 360° central angle -  85π ft2
then the area for 1° =  85π ft2/360°
the area of 36° sector =  85π ft2/360° x 36°
=  8.5π ft2

7 0

2 years ago

Stacey went to six different auto repair shops to get the following estimates to repair her car.

topjm [15]

Answer:

534 is the mean.

Step-by-step explanation:

to calculate the mean you add all the numbers together (for example this set of numbers):

785, 585, 465, 409, 495, 465

=3204

then divide the number of numbers that you added together , (in this case 6)

3204/6

534

5 0

2 years ago