Answer:
c = 80 ÷ 5
Or
5c = 80
Step-by-step explanation:
It's pretty self explanatory. All you have to do is convert the words into an equation.
I would convert -2pi / 3 to degrees first by multiplying by 180degrees / pi. It equals 120 degrees.
120 degrees is in quadrant II, which is 90 degrees plus 30 degrees. It is 60 degrees from the 180 degrees.
So the reference triangle you use is 60 degrees.
Cos60 = 0.5
sin60 = sqrt(3) /2
But in quadrant II the only trig ratio that's positive is sin; all others are negative.
So cos120 = -0.5
sin60 = sqrt(3) /2
<span>Keeping in mind that points on unit circle are (cos, sin), the point is </span>(-0.5, <span>sqrt(3) /2).
</span>
Answer:
13.) 314.2 in²
15.) 181.5 ft²
Step-by-step explanation:
The area of a circle is found using the equation:
A = πr²
In this equation, "π" represents the number pi (3.14....) and "r" represents the radius (half the diameter).
For 13.), you have been given the radius. Thus, you can substitute it into the equation and solve for "A".
A = πr²
A = π(10)²
A = π x (100)
A = 314.2 in²
For 15.), you have been given the diameter. To find the radius, you need to divide this value by 2. Once you find the radius, you can plug it into the equation and simplify like above.
diameter = 15.2 ft
radius = 7.6 ft
A = πr²
A = π(7.6)²
A = π x (57.76)
A = 181.5 ft²
