What are the numbers?

Question

The sum of two numbers is 66. The difference is 8. What are the numbers?

Answer 1

x + y = 66

x - y = 8                     systems of equations by elimination

                                  x = one of the numbers and y = the other

                                  since the y in the first equation is 1y and the y in the second equation is -1y the y's cancel each 

                                  other out.

2x = 74

x = 37

 

37 + y = 66

y = 29

 

37 - 29 = 8

Answer 2

x+y=66

x-y=8       using the elimination method to eliminate y

--------------

2x=74      divide by 2

x=37

then substitute x=37 in the first equation

37+y=66      subtract 37 from both sides

y=29