There are two (equivalent) formulas for the circumference of a circle:
C = 2 pi r, where r is the radius of the circle
C = pi d, where d is the diameter of the circle
In this particular problem, however, we're dealing with arc length. For the shown central angle "theta" = 160 degrees, the arc length is 42 cm.
Knowing this enables us to calculate the radius or diameter of the circle.
Arc length = s = (radius) (central angle, in radians, not degrees)
First, convert 160 degrees to radians: 160 deg pi rad
----------- * ------------ = (8/9) pi rad
1 180 deg
Then 42 cm = r *(8/9) pi rad
Solve for the radius (r): divide 42 cm by (8/9) pi rad
Then use the formula for circumference introduced earlier:
C= 2 pi r Substitute [42 cm / ( (8/9) pi rad )] for r.
Simplify your result, and you will then have the circumference, C, in cm.
Answer:

Step-by-step explanation:
In 2x/(x^2 - 1)1/2

Apply the property of natural log
ln x^m = m ln(x) move the exponent before ln


ln(m/n)= ln m - ln n

multiply 1/2 inside the terms

Answer:
All the members of a construction crew work at the same pace. Four of them working together are able to pour concrete foundations in 32 hours.
Step-by-step explanation:
Sample space = 17 + 7 + 4 = 28
P(pink) = 7/28
P(orange) = 17/28
P(pink or orange) = P(pink) + P(orange)
P(pink or orange) = 7/28 + 17/28
P(pink or orange) = 24/28
P(pink or orange) = 6/7 or 0.857143 or 85.7%
Simplifying
9x + -3(x + 8) = 6x + -24
Reorder the terms:
9x + -3(8 + x) = 6x + -24
9x + (8 * -3 + x * -3) = 6x + -24
9x + (-24 + -3x) = 6x + -24
Reorder the terms:
-24 + 9x + -3x = 6x + -24
Combine like terms: 9x + -3x = 6x
-24 + 6x = 6x + -24
Reorder the terms:
-24 + 6x = -24 + 6x
Add '24' to each side of the equation.
-24 + 24 + 6x = -24 + 24 + 6x
Combine like terms: -24 + 24 = 0
0 + 6x = -24 + 24 + 6x
6x = -24 + 24 + 6x
Combine like terms: -24 + 24 = 0
6x = 0 + 6x
6x = 6x
Add '-6x' to each side of the equation.
6x + -6x = 6x + -6x
Combine like terms: 6x + -6x = 0
0 = 6x + -6x
Combine like terms: 6x + -6x = 0
0 = 0
Solving
0 = 0