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vlabodo [156]
3 years ago
13

Check all that apply. Pi/4 is the reference angle for:

Mathematics
1 answer:
Sergio039 [100]3 years ago
7 0

Reference angle is the angle that is formed by the the terminal side of teh angle and the horizontal line or the x-axis. The reference angles of the different quadrants can be determined using the formula correspondingly:

Quadrant 1: RF = actual angle

Quadrant 2: RF = actual angle - 90 = actual angle - pi/2

Quadrant 3: RF = actual angle - 180 = actual angle - pi

Quadrant 4 : RF = actual angle - 270 = actual angle - 3/4 pi

The first thing to do is to determine the quadrants of each angle and then apply the formula:

a. 19 pi /4 = 855 deg = 2nd Q = 135 + 45 = 180 (correct)

b. 15 pi/4 =  675 deg = 4th Q = 315 + 45 = 360 (correct)

c. 7 pi/4 = 315 deg = 4th Q = 315 + 45 = 360 (correct)

d. 12 pi/4 = 540 deg =  x axis = not correct

Answers are A, B and C.

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Minor surgery on horses under field conditions requires a reliable short-term anesthetic producing good muscle relaxation, minim
andreev551 [17]

Answer:

p_v =P(t_{74}    

If we compare the p value and a significance level for example \alpha=0.1 we see that p_v>\alpha so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, so we can conclude that the true mean it's not significantly less than 20 min.

Step-by-step explanation:

Data given and notation    

\bar X=18.81 represent the average lateral recumbency for the sample    

s=8.4 represent the sample standard deviation    

n=75 sample size    

\mu_o =20 represent the value that we want to test    

\alpha represent the significance level for the hypothesis test.    

t would represent the statistic (variable of interest)    

p_v represent the p value for the test (variable of interest)    

State the null and alternative hypotheses.    

We need to apply a left tailed  test.  

What are H0 and Ha for this study?    

Null hypothesis:  \mu \geq 20  

Alternative hypothesis :\mu < 20  

Compute the test statistic  

The statistic for this case is given by:  

t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}} (1)    

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".    

Calculate the statistic    

We can replace in formula (1) the info given like this:    

t=\frac{18.81-20}{\frac{8.4}{\sqrt{75}}}=-1.227

The degrees of freedom are given by:

df=n-1=75-1=74    

Give the appropriate conclusion for the test  

Since is a one side left tailed test the p value would be:    

p_v =P(t_{74}    

Conclusion    

If we compare the p value and a significance level for example \alpha=0.1 we see that p_v>\alpha so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, so we can conclude that the true mean it's not significantly less than 20 min.

3 0
3 years ago
Evaluate the expression below when x = 4 and y = -2 *
kozerog [31]

Answer:

Evaluate the expression below when x = 4 and y = -2 *

hii your question is incomplete

can you please recheck once

there is no expression given

6 0
3 years ago
13. jewelry marena is using a certain number of blue beads in a bracelet
kherson [118]

The simplest expression that represents the total number of beads in her bracelet design is 2b + 7.

Expression:

An expression is the  sentence with a minimum of two numbers or variables and at least one math operation.

This math operation can be addition, subtraction, multiplication, or division.

The structure of an expression is:

Expression = (Number/variable, Math Operator, Number/variable)

Given,

Jewelry Marena is using a certain number of blue beads in a bracelet

design. she will use 7 more red beads than blue beads.

Here we need to write an expression in simplest form that represents the total number of beads in her bracelet design.

Assign a variable for the unknown value.

Let b be the number of blue beads for the bracelet.

The number of red beads will be represented as b + 7.

Determine the expression for the total number of beads.

Then we can written it as,

=> b + (b +7)

=> 2b + 7.

Therefore, the total number of beads can be written as 2b + 7.

To know more about Expression here.

brainly.com/question/14083225

#SPJ4

3 0
2 years ago
In parallelogram , ABCD ∠A has a measure of 62° . Find the measures of ∠B and ∠C.
Anastasy [175]

Answer:

<C = 62 degrees,  <B= 118 degrees

Step-by-step explanation:

Opposite angles of parallelograms are always congruent.

Consecutive ( angles that are next to each other ) always add up to 180.

180-62=118

5 0
3 years ago
Solve the system of equations by graphing. x+y=-9 4x+y=-19
shutvik [7]

For this case we have the following system of equations:

x + y = -9\\4x + y = -19

We multiply the first equation by -4:

-4x-4y = 36

We have the following equivalent system of equations:

-4x-4y = 36\\4x + y = -19

We add the equations:

-4x + 4x-4y + y = 36-19\\-3y = 17\\y = - \frac {17} {3}

We find the value of the variable "x":

x = -9-yx = -9 - (- \frac {17} {3})\\x = -9 + \frac {17} {3}\\x = \frac {-27 + 17} {3}\\x = - \frac {10} {3}

Thus, the solution of the system is:

(x, y): (- \frac {10} {3}, - \frac {17} {3})

See the graphic in the attached image

ANswer:

(x, y): (- \frac {10} {3}, - \frac {17} {3})

See the graphic in the attached image

4 0
4 years ago
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