You have to get x alone and then do the rest of the steps
Cos 157.5º=-cos (180º-157.5º)=-cos 22.5=-cos(45/2)
cos Ф/2=⁺₋√((1+cosФ)/2).
In this case 157.5º is in the second quadrant, therefore we use the following equation:
cos Ф/2=-√((1+cosФ)/2). (we will have a negative number)
cos 157.5º=-cos (45/2)=-√((1+cos 45º)/2)
=-√((1+√2/2)/2)
=-√((2+√2)/4)
=-√(2+√2) / 2 (≈-0.92387...)
Answer: cos 157.5º= -√(2+√2) / 2
Answer:
3/12 =1/6
Step-by-step explanation:
4+5+3=12
probability of picking 3 marbles is
3/12which in lowest term is 1/6
<h3>
Answer: 18pi</h3>
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Explanation:
The area 81pi square meters leads to the radius 9 meters
Use the formula A = pi*r^2 to see why this is the case. You plug in A = 81pi and solve for r to get r = 9.
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Once you know the radius, you can determine the circumference C
C = 2*pi*r
C = 2*pi*9
C = 2*9*pi
C = 18pi
The circumference is the perimeter, or distance, around the circle.
Answer:
C. Claire has 10 country CDs and 5 Jazz CDs
Step-by-step explanation:
means that 10 out of 15. So we can assume that in total she has 15 CDs and 10 of them are Country and the other is Jazz.
This would rule out choice D.
If we reduce this fraction then we would have:
This means that two-thirds of her CDs are country music. So this would rule out A and B choices.
Now C is correct because 10 country plus 5 Jazz is equal to 15 CDs. So we have the correct total.
The answer is C.
