What is the exact value of cos 22.5°?

Answers

Answer 1

Answer: $cos( (x)/(2) )= \pm \sqrt{ (1+cosx)/(2) } \n\n cos( (45)/(2) )= \pm \sqrt{ (1+cos(45))/(2) } \n\n cos( 22.5)= \pm \sqrt{ (1+ ( √(2) )/(2) )/(2) } \n\n cos( 22.5)= \pm \sqrt{ ( (2+ √(2) )/(2) )/(2) } \n\n cos( 22.5)= \pm \sqrt{ {( 2+√(2) )/(2)* (1)/(2) }} \n\n cos( 22.5)= \pm \sqrt{ {( 2+√(2) )/(4)}} \n\n cos(22.5)= \pm \frac{ \sqrt{2+ √(2) } }{2}$

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Find the value of x. 60o

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Answers

180-2(55)-x=0
180-110-x=0
70-x=0
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An open box will be made from a rectangular piece of cardboard that is 8 in. by 10 in. The box will be cut on the dashed red lines, removing the corners, and then folded up on the dotted lines. What is the MAXIMUM possible volume for the box?A) 1.5 in3
B) 5.8 in3
C) 52 in3
D) 64 in3

Answers

The correct answer is this one: "C) 52 in3."

Given the illustration, we can be able to know the dimensions of the formed box.

The dimensions are
Length: 10 - 2x
Width: 8 - 2x
Height: x

So the volume is
Volume = (10-2x) * (8-2x) * (x)
Let x = 2.5
Volume = (5) * (3) * (2.5) = 37.5
Let x = 2
Volume = (6) * (4) * (2) = 48
Let x = 1.5
Volume = (7) * (5) * (1.5) = 52.5
Let x = 1
Volume = (8) * (6) * (1) = 48
Let x = 0.5
Volume = (9) * (7) * (.5) = 31.5

The Correct answer is A I took the test

Step-by-step explanation:

Kara graphed a system of linear equations. The two lines are parellel and they do not coincide which statement about the number of points that satisfy the system is true? A.no points satisfy both equations B. one point satisfies both equations C.two points satisfy both equations D.An infinite number of points satisfy both equations

Answers

the answer is A thanks for asking

I believe that the answer is (a) no points satisfy both equations. Hope this helped☻

Mary has 18 coins with a total value of $2.85. If the coins are dimes and quarters,how many of each type of coins does Mary have

Answers

$x-dimes\ny-quarters\n\n \left\{\begin{array}{ccc}x+y=18\n0,1x+0.25y=2.85&/\cdot(-10)\end{array}\right\n+\left\{\begin{array}{ccc}x+y=18\n-x-2.5y=-28.5\end{array}\right\n------------\n.\ \ \ \ \ \ -1.5y=-10.5\ \ \ \ /:(-1.5)\n.\ \ \ \ \ \ \ \ \ \ \ \ \ y=7\n\nx+7=18\nx=18-7\nx=11\n\nAnswer:11\ dimes\ and\ 7\ quarters$

Let's say x represents the number of dimes and y represents the number of quarters.

Note: A dime is worth 10 cents and a quarter is worth 25 cents. Therefore, their coefficients would be 0.1 and 0.25 (you must divide them by 100, since 1 dollar = 100 cents).

Now you can set up a system of equations and solve by substitution.

x + y = 18
0.1x + 0.25y = 2.85

In order to substitute, you have to solve for one of the variables in terms of the other. This will be easiest to do with the first equation.

x + y = 18
y = 18 - x

Now, substitute in that value of y into the second equation.

0.1x + 0.25(18 - x) = 2.85

Now, you can solve for x.

0.1x + 4.5 - 0.25x = 2.85
- 0.15x = -1.65
x = 11

You have 11 dimes.

Now you can substitute that value into your original first equation.

(11) + y = 18
y = 7

You have 7 quarters.

Answer: 11 dimes and 7 quarters

Paul took a 140 miletrip on his motorcycle. If he drove 60% of his trip on the first day,how many miles did Paul drive one day one

Answers

140/100 x 60 which gives you 84 miles

If x-3 is 4 more than w, then x is how much more than w?

Answers

Well, what I do is actually substitute in numbers. So what I did was x= 3 and made then did the subtraction. Afterwards I got x = 0. Since x= w+4 you would want to subtract four to get the distance. Afterwards you get 3 (x) is ? than w= - 4 and thats 7 (7 is the answer)

Answer:

definitely 7

Step-by-step explanation:

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