Cyndie M. answered 10/18/19
Math / Science Tutor: Middle School, High School, College, Homeschool
the difference of two numbers is 3 is represented by: x - y = 3
their sum is 13 is represented by: x + y = 13
we now have a system of equations:
x - y = 3
x + y = 13
Using the elimination method the y's cancel out, add the remaining like terms to get:
2x = 16
divide by 2:
x = 8
Now substitute x = 8 back into either one of the original equations
x + y = 13
8 + y = 13
subtract 8 from both sides to get
y = 5
So the solution to the system is (8, 5)
x = 8 and y = 5