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3 years ago

Which of the following statements is true?

Mathematics

1 answer:

saveliy_v [14]3 years ago

3 0

Answer:

The answer is d.

Step-by-step explanation:

As we know, sin x= cos (90°-x)

sin 18° = cos (90°-18°)

= cos 72°.

Similarly, sin 72°= cos (90°-72°)

= cos 18°

But, sin 55°= cos (90°-55°)

= cos 35°

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Given: △CGF ,CG=GF=CF=and, KOPS is a square inside this triangle with one side on CF and its two vertices on CG and GF

shepuryov [24]

Answer:

AKPOS/ACGF = 28√3 -48 ≈ 0.497423

Step-by-step explanation:

Let's assume the square is a unit square. Then the height of the triangle is ...

1 +(√3)/2 = h

and half the base of the triangle is ...

h/√3 = (√3)/3 +1/2 = b/2

The area of the triangle is the product of these:

A = (1/2)bh

= (2 +√3)/2 × (3 +2√3)/6

= (6 +3√3 +4√3 +6)/12 = (12 +7√3)/12

So, the ratio of the area of the square to that of the triangle is the inverse of this, or ...

(square area)/(triangle area) = 12/(12+7√3)

(square area)/(triangle area) = 28√3 -48

8 0

3 years ago

a ribbion is 3 2/3 yards long. Mae needs to cut the ribbion into pieces that are 2/3 yard long.how much ribbion will be left aft

Lemur [1.5K]

To answer this question you need to divide to get the number of pieces and then multiply whats leff by 3 2/3.

Divide 3 2/3 by 2/3. There are a few ways to do this but I am going to turn 3 2/3 into an improper fraction and then divide.

So $3\frac{2}{3} = \frac{11}{3}$
Now divide
$\frac{\frac{11}{3}}{\frac{2}{3}}$
$\frac{11}{3} \times \frac{3}{2} = \frac{11}{2} = 5\frac{1}{2} = 5.5$

We can see she can get 5.5 pieces at 2/3. So .5 is going to be left over so we ask our self, what is .5 of 3 2/3? We times .5 by 3 2/3 = 1.83 yards left. If you want it into a fraction, it would be $1\frac{83}{100}$ yards left

7 0

3 years ago

Find all solutions in the interval [0,2pi) sec^2x + 2tanx = 3

Marysya12 [62]

Tan^2x + 1 + tanx - 3 = 0 tan^2x + tanx - 2 = 0 (tanx + 2)(tanx - 1) = 0 tanx = -2 or tanx = 1 x = 2.034 radians or x = 5.176 radians or x = pi/4 radians or x = 5pi/4 radians

6 0

3 years ago

Roberta has $10,540 to invest. She plans to invest her money in certificates of deposit (CDs) that have 2.1% interest, a stock p

ira [324]

Answer:

The amount invested in CDs is $1,340

The amount invested in the stock portafolio is $6,900

The amount invested in the saving accounts is $2,300

Step-by-step explanation:

Let

x ---->the amount invested in CDs at 2.1%

y ---> the amount invested in the stock portfolio at 2.5%