Answer:
cos(a + b) = 
Step-by-step explanation:
cos(a + b) = cos(a).cos(b) - sin(a).sin(b) [Identity]
cos(a) = 
cos(b) = 
Since, terminal side of angle 'a' lies in quadrant 3, sine of angle 'a' will be negative.
sin(a) =
[Since, sin(a) =
]
= 
= 
Similarly, terminal side of angle 'b' lies in quadrant 2, sine of angle 'b' will be negative.
sin(b) =
= 
= 
By substituting these values in the identity,
cos(a + b) = 
= 
= 
= 
Therefore, cos(a + b) = 
Answer:
23.7°
9.1~ft
Step-by-step explanation:
Formula for the area of a sector of central angle n (in degrees) and radius r:

We have:
A = 100 ft^2
r = 22 ft
We need to find:
r


The central angle measures 23.7°.
Formula for the length of an arcs of a circle with central angle n (in degrees) and radius r:

We have:
n = 23.7°
r = 22 ft
We need to find:
s


Answer:
should be added to the given equation.
Step-by-step explanation:
Let a is added to the given equation.
According to the given condition,

So,
should be added to the given equation.
The estimate would be 2+3 5+2 and 6+1
so 577
you can also just round and do 250 +300= 550 +20=570
Answer:
250 students at a minimum must attend to meet the student council goal.
Step-by-step explanation:
divide 500 by 2. you get 250 students that pay $2 each that equals $500.