I need Unit 3 parallel and perpendicular lines Homework 5 slope of lines it’s due today!

If 180° < α < 270°, cos⁡ α = −817, 270° < β < 360°, and sin⁡ β = −45, what is cos⁡ (α + β)?

eduard

Answer:

$cos(\alpha+\beta)=-\frac{84}{85}$

Step-by-step explanation:

we know that

$cos(\alpha+\beta)=cos(\alpha)*cos(\beta)-sin(\alpha)*sin(\beta)$

Remember the identity

$cos^{2} (x)+sin^2(x)=1$

step 1

Find the value of $sin(\alpha)$

we have that

The angle alpha lie on the III Quadrant

so

The values of sine and cosine are negative

$cos(\alpha)=-\frac{8}{17}$

Find the value of sine

$cos^{2} (\alpha)+sin^2(\alpha)=1$

substitute

$(-\frac{8}{17})^{2}+sin^2(\alpha)=1$

$sin^2(\alpha)=1-\frac{64}{289}$

$sin^2(\alpha)=\frac{225}{289}$

$sin(\alpha)=-\frac{15}{17}$

step 2

Find the value of $cos(\beta)$

we have that

The angle beta lie on the IV Quadrant

so

The value of the cosine is positive and the value of the sine is negative

$sin(\beta)=-\frac{4}{5}$

Find the value of cosine

$cos^{2} (\beta)+sin^2(\beta)=1$

substitute

$(-\frac{4}{5})^{2}+cos^2(\beta)=1$

$cos^2(\beta)=1-\frac{16}{25}$

$cos^2(\beta)=\frac{9}{25}$

$cos(\beta)=\frac{3}{5}$

step 3

Find cos⁡ (α + β)

$cos(\alpha+\beta)=cos(\alpha)*cos(\beta)-sin(\alpha)*sin(\beta)$

we have

$cos(\alpha)=-\frac{8}{17}$

$sin(\alpha)=-\frac{15}{17}$

$sin(\beta)=-\frac{4}{5}$

$cos(\beta)=\frac{3}{5}$

substitute

$cos(\alpha+\beta)=-\frac{8}{17}*\frac{3}{5}-(-\frac{15}{17})*(-\frac{4}{5})$

$cos(\alpha+\beta)=-\frac{24}{85}-\frac{60}{85}$

$cos(\alpha+\beta)=-\frac{84}{85}$

4 0

3 years ago

5 kilograms of coffee are going to be shared equally among 4 people.

kherson [118]

Step-by-step explanation:

I'm not sure if this will help but to find out how much coffee 4 people would need you would have to divide 4 into 5 which is 1 1/5

EQUATION-- 4/5= X

I chose that because / means divide 5 into 4 would give you x we don't know what x is until we actually do the problem

Even if im not correct I hope it helped a bit

5 0

2 years ago

The number 42 is increased to 46. what is the percentage by which the number was increased?

Arte-miy333 [17]

Answer:

9.52% ( to 2 dec. places )

Step-by-step explanation:

Calculate the percentage increase using

percent increase = $\frac{increase}{original}$ × 100%

increase = 46 - 42 = 4, hence

percent increase = $\frac{4}{42}$ × 100% ≠ 9.52%

7 0

2 years ago

State the slope and the y-intercept for the graph of the equation. y= -2

kotegsom [21]

Answer: 0; -2

Step-by-step explanation:

Data: y-intercept=x and slope=x

Equation=y=-2

Only step, Point out the y-intercept and slope

-2=y-intercept

0=slope

Reason: Since there is no visible slope, the placeholder would be 0 therefore the slope would be 0, -2 is the only number left so that means the only number that can be y-intercept is -2.

That is why the slope is 0 and the y-intercept is -2

I hope this helps!

5 0

2 years ago

If you are self-employed, you don't have to pay FICA on all your salary, just on 92.35% of it. If your salary is $128,255 what i

Artist 52 [7]

Answer:

The amount that I am required to pay monthly as FICA if my salary remains constant is $18,121.85¢

Step-by-step explanation:

Federal insurance contributions act is a law that mandates all employers of labour to withhold medicare and certain taxes from the wages that are paid to employees or workers. These taxes are remitted to the government later which is then used for the provision of basic amenities and quality health care.

Since, I am only required by law to pay FICA on only 92.35% of my monthly salary, we need to calculate the the actual amount that makes up 92.35 percent of my monthly salary.

If $128,255 is my current monthly salary, then 92.35% of it will be:

92.35/100 × 128,255

= 0.9235 × 128,255

= $118,443.49¢

This is the part of his monthly salary that he is required by law to pay FICA on.

Then, if FICA is 15.3% of a worker's taxable income, then I am required to pay 15.3% of the taxable $118,443.49¢ since I am self employed and mustn't pay it on the entire $128,255 that I earn monthly.

My monthly FICA contribution is then:

15.3/100 × 118,443.49

= 0.153 × 118,443.49

= $18,121.85¢.

Therefore, if my salary remains constant, the amount that I am required by law to pay monthly as FICA is $18,121.85

6 0

3 years ago

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I need Unit 3 parallel and perpendicular lines Homework 5 slope￼ of lines it’s due today!

I need Unit 3 parallel and perpendicular lines Homework 5 slope of lines it’s due today!