Answer:
m<A = 72 degrees
m<B = 108 degrees
Step-by-step explanation:
For the parallelogram ABCD
The sum of the opposite angle will be 180 degrees
Hence <A + <B = 180 and m<A = m<C
5y - 3 = 3y + 27
5y - 3y = 27 + 3
2y = 30
y = 30/2
y = 15
Get m<A
m<A = 5y - 3
m<A = 5(15)-3
m<A = 75 - 3
m<A = 72 degrees
Get m<B
From the equation above;
m<B = 180 - m<A
m<B = 180 - 72
m<B = 108degrees
Answer: a) 
b) Cost of a macadamia nut chip cookie is $33.93 and the cost of triple chocolate cookie. is $3.77
c) Elimination method because it enables us to eliminate one of the variables.
Step-by-step explanation:
Let x be the cost of macadamia nut chip cookie and y be the cost of triple chocolate cookie.
Then according to the question we have the following equations:-

Multiplying 5 on both sides of the equation (2), we get
...............(3)
By using elimination method, subtract equation (1) from (3) we get

Substitute the value of y in (2), we get

We have to find the exact value of: arc cos ( sin ( π /6 ) ).
We know that:
sin ( π/6 ) = sin 30° = 1/2
Arc cos is the inverse function of cosine.
arc cos ( 1/2 ) = 60° = π/3
<span>A common factor is a factor of 2 or more numbers.
the factors of 12 are: 1,2,3,4,6,12
the factors of 21 are: 1,3,7,21
1 and 3 are both common factors of 12 and 21.</span>