The sum of two numbers is 15 and the difference is 31. Write a system using x and y and then solve. HELP!

The sum of two numbers is 15 and their difference is 31. 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 15. In other words, x plus y equals 15 and can be written as equation A:

x + y = 15

The difference between x and y is 31. In other words, x minus y equals 31 and can be written as equation B:

x - y = 31

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

x - y = 31

x = 31 + y

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

x + y = 15

31 + y + y = 15

31 + 2y = 15

2y = -16

y = -8

Now we know y is -8. Which means that we can substitute y for -8 in equation A and solve for x:

x + y = 15

x + -8 = 15

X = 23

Summary: The sum of two numbers is 15 and their difference is 31. What are the two numbers? 23 and -8 as proven here:

Sum: 23 + -8 = 15

Difference: 23 - -8 = 31

Step-by-step explanation:

stop cheating

step-by-step explanation:

step-by-step explanation:

no, her answer is not correct.   we square the lengths of all sides and then determine whether the pythagorean theorem holds here:

9² + 15² = 306.   this is not equal to the square of the longest side ( that square being 395.   answer c is correct.