Answer:

Step-by-step explanation:
Given

Required
Use the expression to prove a trigonometry identity
The given expression is not complete until it is written as:

Going by the Pythagoras theorem, we can assume the following.
- a = Opposite
- b = Adjacent
- r = Hypothenuse
So, we have:


Having said that:
The expression can be further simplified as:

Substitute values for sin and cos
becomes

Answer:
Step-by-step explanation:
Sara's base pay is $80
(a) The 9t represents the additional amount of money that she earns if she gives instruction for t hours. 9 stands for $9 per hour
b)The term in the expression is t which stands for the number of hours that she instructs. The coefficient is 9 which stands for the hourly rate
c) The expression for 7 hours would be
We will substitute t into 80 + 9t. It becomes
80 + 9×7
d) in all, she will earn
80 + 9×7 = $143
Since 16 and 25 are perfect squares you can factor the first part.
4^2-5^2(b+3)^2
=(4-5(b+3))(4+5(b+3))
=(4-5b-15)(4+5b+15)
=(-11-5b)(19+5b)
Which can be expanded if necessary,
= -209+150b-25b^2
Answer:
Step-by-step explanation:
two step equation
n - 5/2 = 5
n = 5 + 5/2
n = 5 + 2.5
n = 7.5
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check
7.5 - 5/2 = 5
7.5 - 2.5 = 5
5 = 5
the answer is good