The Sum of Two Numbers is 85 and Their Difference is 4

The sum of two numbers is 85 and their difference is 4. What are the two numbers? Let's start by calling the two numbers we are looking for x and y.

The sum of x and y is 85. In other words, x plus y equals 85 and can be written as equation A:

x + y = 85

The difference between x and y is 4. In other words, x minus y equals 4 and can be written as equation B:

x - y = 4

Now solve equation B for x to get the revised equation B:

x - y = 4
x = 4 + y

Then substitute x in equation A from the revised equation B and then solve for y:

x + y = 85
4 + y + y = 85
4 + 2y = 85
2y = 81
y = 40.5

Now we know y is 40.5. Which means that we can substitute y for 40.5 in equation A and solve for x:

x + y = 85
x + 40.5 = 85
X = 44.5

Summary: The sum of two numbers is 85 and their difference is 4. What are the two numbers? Answer: 44.5 and 40.5 as proven here:

Sum: 44.5 + 40.5 = 85
Difference: 44.5 - 40.5 = 4

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The Sum of Two Numbers is 85 and Their Difference is 5
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