We will have a system of equations, and we are going to solve it by using substitution.
Let's make the equations.
x+y+z=2100
z+y=x
Since y and z are equal, I think it is easier for us to have them as one variable for now. Let the value of z and y be a.
These are the equations now.
x+2a=2100
2a=x
Since the second equation is giving the value of x, let it replace the value of x also in the first equation.
2a+2a=2100
4a=2100
2100÷4= 525
so, x and y equal 525. Let's put this in our original equation.
x+525+525=2100
x+ 1,050= 2,100
x= 1,050
So, x=1,050, y= 525 =z.
Answer: Choice B

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Work Shown:

This points us to answer choice B
The answer is 3/16 because half of 3/8 is 3/16
Answer:
The mean (average) of a data set is found by adding all numbers in the data set and then dividing by the number of values in the set. The median is the middle value when a data set is ordered from least to greatest. The mode is the number that occurs most often in a data set.
Answer:
A) SUBTRACT 3x by both sides of the bottom equation.