Answer:
The given expression in simplified form is: 
Step-by-step explanation:
Simplifying the expression involve reducing the number of terms to minimum and making the expressions in standard form.
This may involve addition, subtraction and multiplication of variables.
Given expression is:

Distributing 5x will give us:

Hence,
The given expression in simplified form is: 
Step-by-step explanation:
15=2c+7
15-7=2c
8=2c
8/2=c
4=c
c=4
Step-by-step explanation:commutative property
hope it helps
Answer:
The equivalent trigonometric ratio in Quadrant I is 
Step-by-step explanation:
The terminal side of
is in the 3rd quadrant.
The principal angle is
In other words, the terminal side of
makes an acute angle of
radian with the positive x-axis. Acute angles are in the first quadrant.
Since the cosine ratio is negative in the 3rd quadrant,
