Answer: They will charge same amount for 360 minutes of calls.
Step-by-step explanation:
A phone company offers two monthly plans plan A cost $9 Plus And additional 0.12 $ for each minute of calls. Plan B cost $27 plus an additional $0.07 for each minute of calls
For what amount of calling do the two plans cost the same?
Let the each minute of calls be 'x'.
So, for plan A would be
plan A cost $9 Plus And additional 0.12 $ for each minute of calls is expressed as

Plan B cost $27 plus an additional $0.07 for each minute of calls is expressed as

According to question, it becomes,

Hence, they will charge same amount for 360 minutes of calls.
Answer:
20
Step-by-step explanation:
You use the distributive property.
Distribute the 2 to whatever is inside the parentheses. (You will multiply)
4×2=8
2×6=12
Substitute the answers above into the parentheses.
(8+12)=20
Hi there!

We are given:
cos(7x)cos(4x) = -1 - sin(7x)sin(4x)
Begin by moving all terms with variables to one side:
cos(7x)cos(4x) + sin(7x)sin(4x) = -1
The corresponding trig identity is cos(A - B). Thus:
cos(7x - 4x) = cos(7x)cos(4x) + sin(7x)sin(4x) = -1
cos(3x) = -1
cos = -1 at π, so:
3x = π
x = π/3
We can also find another solution. Let 3π = -1:
3x = 3π
x = π
Thus, solutions on [0, 2π) are π/3 and π.