Answer:

Step-by-step explanation:
we know that

Remember the identity

step 1
Find the value of 
we have that
The angle alpha lie on the III Quadrant
so
The values of sine and cosine are negative

Find the value of sine

substitute




step 2
Find the value of 
we have that
The angle beta lie on the IV Quadrant
so
The value of the cosine is positive and the value of the sine is negative

Find the value of cosine

substitute




step 3
Find cos (α + β)

we have




substitute



Answer:
see explanation
Step-by-step explanation:
A recursive rule allows us to find the term in a sequence from the previous term.
From the given geometric sequence find r the common ratio
r =
=
= - 4
Hence recursive rule is
= - 4
( a₁ =
)
Answer:
Step-by-step explanation:
-3x + 4y = -18
8x - 4y = 28
5x = 10
x = 2
4 - y = 7
-y = 3
y = -3
(2, -3)
Answer:
2(n + m)
Step-by-step explanation:
Answer:
The numbers needed to fill each box are in the image attached
Step-by-step explanation:
The probability of the coin landing on heads is 2/7, so the probability of it landing on tails is 1 - 2/7 = 5/7
The probability of landing heads 2 times is:
P = (2/7) * (2/7) = 4/49
The probability of landing heads and then tails is:
P = (2/7) * (5/7) = 10/49
The probability of landing tails and then heads is:
P = (5/7) * (2/7) = 10/49
The probability of landing tails 2 times is:
P = (5/7) * (5/7) = 25/49
The numbers needed to fill each box are in the image attached.