Question 59399
Hi Sher,
Solve and show the equation used for the solution:

   The sum of two numbers is 40.  Their difference is 8.  Find the two numbers.
:
Sum means add and difference means subtract.
Let one number be:x  and the other be:y

x+y=40
x-y=8
Add the two equations and the y's are eliminated.
x+y=40
x-y=8
______
2x+0=48
2x=48
2x/2=48/2
x=24
Substitute that in for x in one of the equations and solve for y.
24+y=40
-24+24+y=40-24
0+y=16
y=16
One number is: 24 and the other is 16
If you aren't using two equations and two unknowns yet, let me know and I'll edit this.  I know I have answered a lot of your questions.  I remember that you were graphing, but I don't remember if you were graphing two lines at the same time.
Happy Calculating!!!