Hi there! f(18) makes the value of x 18 and x is the number of movies watched in 1 month. Therefore, A and C are eliminated because we’re talking 18 movies, not 18 months. B is also out, because Kelsey would pay more than $27 a month for the service, especially with the service fee. 18 * 1.50 is 27 and 27 + 12.50 is 39.50. Kelsey spends $39.50 a month watching 18 movies per month. The answer is D.
Answer: 
Step-by-step explanation:
Given
The ratio of mixture of sand and cement is 5:3
If the total volume of mixture is 
Suppose there is 5x and 3x cubic centimeter of sand and cement respectively i.e.

Sand 
So, there is
of sand in the mixture
We are trying to represent the change in position of a bird flying down 7 ft to the ground.
Often, for the y axis- up is positive and down is negative.
Change in position is displacement- how far it was from the starting point
( different from distance which is how far is traveled
ex. doubling back would have distance they traveled some distance while the displacement is 0 because they are back to where they started).
The bird is going down 7 ft from where it originally was, which can be represented by
Bird's displacement = -7 ft
Answer:
2/3 [3x - 15] =x-10
open the brackets first
[2/3 x3x] -[2/3 x15 =x - 15
2x - 10 =x - 10
put the like terms together
2x -x =-10 +10
x=0
Step-by-step explanation: