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erastova [34]
2 years ago
7

Question is 15 points

Mathematics
1 answer:
mihalych1998 [28]2 years ago
4 0

This is a doozy so pay attention. First thing you have to recognize is that is a trig identity, the sum identity for cosine to be exact. That formula is

cos(\alpha +\beta )=cos\alpha cos\beta -sin\alpha sin\beta.

So that means you need to find the cosine of alpha and the sin of beta. We are given the sin of alpha being 4/5 in the first quadrant. If you set up the sin ratio which is side opposite over hypotenuse of a right triangle, you put the 4 on the side opposite the reference angle, alpha, and the hypotenuse of 5 on the terminal ray and then you have to find the missing side of the right triangle you created. Using Pythagorean's theorem, you find that the missing side, which is the adjacent side to alpha, is 3. Now you can find the cosine of alpha as well, since cosine is the side adjacent, 3, over the hypotenuse, 5. So far wwe have

sin\alpha =\frac{4}{5} and

cos\alpha =\frac{3}{5} for that first angle. Now moving on to the second angle. The cosine of beta is side adjacent, 5, over the hypotenuse, 13, and we are missing the side opposite the reference angle beta. Using Pythagorean's theorem again to find the side opposite, we have that that side measures 12. Now we can find the sine of beta using that opposite side, 12, over the hypotenuse, 13. What we have now is

cos\beta =\frac{5}{13} and

sin\beta =\frac{12}{13}. According to the identity, we have to multiply those ratios now:

(\frac{3}{5}*\frac{5}{13})-(\frac{4}{5}*\frac{12}{13}).

When you do that you get

\frac{3}{13}-\frac{48}{65}.

Of course in order to subtract those 2 fractions you need a common denominator which is 65 so

\frac{15}{65}-\frac{48}{65} which gives you a final answer of -\frac{33}{65} which is the first choice given above. There you go!

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abruzzese [7]

Answer:

<u>29/48</u>

Step-by-step explanation:

3 5/8  Divided By 6= 29/48

Dividing fractions is simple if you know what to do, and how to multiply.

Here's how:

-----------------------------

<u><em>1. convert any whole number or mixed number into a fraction.</em></u>

<em>6 = 6/1.</em>

Whole number <u><em>x</em></u> denominator <u><em>+ </em></u>numerator = <em><u>29/8</u></em>

 (3)                              (8)                       (5)         (answer/original denominator)

-----------------------------

<u><em>2. Keep, Change, Flip (KCF)</em></u>

29             1

__      x     __

8                6

With KCF, we keep the first fraction, change the division to multiplication, and flip the second fraction.

---------------------------------------

<em><u>3. Multiply numerators and denominators</u></em>

29 x 1 =      29

                  __

8 x 6   =     48

29/48 is in it's simplest form.

Hence, your answer.

<h2><u><em>Each wired piece was 29/48 of a yard.</em></u></h2><h2 /><h2 /><h2 /><h3><u><em>P.S  -  Please let me know if i made any mistakes.</em></u></h3>
7 0
2 years ago
The cost of a student ticket is $7 write a equation that correctly relates the total cost
daser333 [38]
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Write the equation <br> it passes through (0,-2) and is perpendicular to the graph of y=5x+7
romanna [79]

Step-by-step explanation:

the line passes through (0,-2) and perpendicular to the graph of y=5x+7.

solution :

the slope = -1/5

the equation :

y+2 = -1/5 (x-0)

y = -1/5x - 2

6 0
2 years ago
Why does everyone expect people to awnser questions but they never awnser any them selves like I need help and I've helped loads
Gnoma [55]

Answer:

thats crazy bro

Step-by-step explanation:

6 0
2 years ago
Read 2 more answers
Please help me in this one
ANEK [815]
The best choices are table 1.

All the input values are being multiplied by themselves by the output values.

This creates a congruent and linear correlation and congruence. 

I hope this helps!

Brainliest answer is always appreciated!
8 0
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