Try this solution, note, checking was not performed.
a. The first variable is x and the second variable is y.
b. The equations are
and 
Step-by-step explanation:
Step 1:
The first step is to define the variables. The variables can be any two symbols, letters, characters, etc.
Here let the first variable be x and the let the second variable be y.
So the variables are defined as x and y.
Step 2:
The sum of the given variables is 12.
The first variable + the second variable = 12,

The difference between the two variables is 4.
The first variable - the second variable = 4.

Step 3:
If we add both the equations we get,
and 
x = 8 and y = 4.
If you were to smplify you would get -6 x (3w+y-6) then yo
Hi there!
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I believe your answer is:
18in³
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Here’s why:
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Assuming that the figure is a rectangular prism:
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Hope this helps you. I apologize if it’s incorrect.
Answer:
41 and 42
Step-by-step explanation:
Let the integers be x and x + 1
=> x + x + 1 = 85
=> 2x + 1 = 85
=> 2x = 84
=> x = 84/2
=> x = 41
Integers are :
41 and 42