we know that
A relationship between two variables, x, and y, represent a direct variation if it can be expressed in the form y/x=k or y=kx
so
we have
a) for x=1 y=0.50--------> y/x=0.50/1------> 0.50
b) for x=2 y=1--------> y/x=1/2-------> 0.50
c) for x=3 y=1.50--------> y/x=1.50/3-----> 0.50
d) for x=5 y=2.50--------> y/x=2.50/5----> 0.50
the value of k is equal to 0.50
so
<span>the relationship forms a direct variation. </span>
the equation is
y=0.50*x
Verify
for x=1
y=0.50*(1)------> y=0.50-----> is correct
for x=2
y=0.50*(2)------> y=1.00-----> is correct
for x=3
y=0.50*(3)------> y=1.50-----> is correct
for x=5
y=0.50*(5)------> y=2.50-----> is correct
For this case we have the following system of equations:

To solve, we clear "x" from the second equation:

We substitute "x" in the first equation:

We clear the value of the variable "y":

We look for the value of the variable "x":

Thus, the solution of the system is given by:

Answer:

Option D
18 - 2[x + (x-5)]
First I would get rid of the inside parenthesis by distributing the + to everything inside and end up with;
18 - 2[x + x - 5]
Then I'd combine like terms inside the brackets
18 - 2[2x - 5]
Then I'd multiply what is inside the brackets by the -2
18 - 4x + 10
I'd combine like terms and end up with:
28 - 4x......or rewritten as -4x + 28
Answer:
76,105
Step-by-step explanation: