1. You got it right.
4π/9 x 180/π = 80°
2. To get a coterminal angle you start with your angle and then you add or subtract 360° (one cycle around the circle).
-123+360+360 = 597°
-123-360 = -483°
3. The angle is 215° from the point (1,0) on the unit circle. The angle 215° is between 180° and 270° so it is in quadrant 3.
So,
"The sum of five times a number and -6"
5n + -6 or 5n - 6
"is -2"
= -2
5n - 6 = -2
Add 6 to both sides.
5n = 4
Divide both sides by 5.
Set up a proportion: x/y = x/y
(.75)/(15) = (x)/(25)
Then cross multiply:
(.75)(25) = (15)(x)
18.75 = 15x
x = 1.25 or (5/4)
There you go :)
C = 2πr Divide both sides by 2π
C/2π = r Switch the sides to make it easier to read
r = c / 2π
Answer:
find the difference. find the sum
Step-by-step explanation: