Double angle identity for sine:


Factorize the left side.

Pythagorean identity:


so that

Answer:
The solution of the system is the ordered pair (-13,-4)
Step-by-step explanation:
we have
-----> equation A
----> equation B
Solve the system by elimination
Multiply by 2 both sides equation B
----> equation C
Adds equation A and equation C

<em>Find the value of a</em>
substitute the value of b in any equation (i take equation B)



therefore
The solution of the system is the ordered pair (-13,-4)
Answer:
2.4
Step-by-step explanation:
The answer will be $13.72 for 7 bags of popcorn.
to find this answer, you first take 5.88 and divide it by 3 to find out how much one bag costs.
the answer to 5.88/3 is 1.96, so you multiply 1.96 by 7 to get the answer of how much 7 bags of popcorn will cost.
hope this helps!