The Sum of Two Numbers is 4 and Their Difference is 99

The sum of two numbers is 4 and their difference is 99. 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 4. In other words, x plus y equals 4 and can be written as equation A:

x + y = 4

The difference between x and y is 99. In other words, x minus y equals 99 and can be written as equation B:

x - y = 99

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

x - y = 99
x = 99 + y

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

x + y = 4
99 + y + y = 4
99 + 2y = 4
2y = -95
y = -47.5

Now we know y is -47.5. Which means that we can substitute y for -47.5 in equation A and solve for x:

x + y = 4
x + -47.5 = 4
X = 51.5

Summary: The sum of two numbers is 4 and their difference is 99. What are the two numbers? Answer: 51.5 and -47.5 as proven here:

Sum: 51.5 + -47.5 = 4
Difference: 51.5 - -47.5 = 99

Sum Difference Calculator
Do you want the answer to a similar problem? Enter the sum and difference here to find the two numbers:

The Sum of Two Numbers is 5 and Their Difference is 1
Using what you learned on this page, try to figure out the next problem on our list and then go here to check the answer.