SOLUTION: The sum of two numbers is 5, and the difference of the numbers is 3. write a system of equations to represent this situation. I know the numbers are 1 and 4, but I don't get ho

Algebra ->  Linear-equations -> SOLUTION: The sum of two numbers is 5, and the difference of the numbers is 3. write a system of equations to represent this situation. I know the numbers are 1 and 4, but I don't get ho      Log On


   



Question 1009649: The sum of two numbers is 5, and the difference of the numbers is 3. write a system of equations to represent this situation.
I know the numbers are 1 and 4, but I don't get how you put them in to a system of equations form.
please help

Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
.
x and y are the numbers
.
x-y=3
x=y+3 . Use this to substitute for x below.
.
x+y=5 . Substitute for x from above
(y+3)+y=5
2y=2
y=1
.
x=y+3
x=1+3
x=4
________________________________
OR:
________________________________
x+y=5
x-y=3 . Add the two equations
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2x=8
x=4
.
x+y=5
4+y=5
y=1
.
CHECK:
x-y=3
4-1=3
3=3