SOLUTION: Please help me solve this problem using substitution? Find the value of two numbers if their sum is 12 and their difference is 4. x+y=12 x-y=4

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Please help me solve this problem using substitution? Find the value of two numbers if their sum is 12 and their difference is 4. x+y=12 x-y=4      Log On


   

Question 536674: Please help me solve this problem using substitution? Find the value of two numbers if their sum is 12 and their difference is 4.
x+y=12
x-y=4
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +x+%2B+y+=+12+
(2) +x+-+y+=+4+
---------------
(2) +x+=+y+%2B+4+
Substitute this value of x
into equation (1)
(1) +%28+y+%2B+4+%29+%2B+y+=+12+
(1) +2y+=+12+-+4+
(1) +2y+=+8+
(1) +y+=+4+
Substitute this back into either (1) or (2)
(2) +x+-+4+=+4+
(2) +x+=+8+
The solution is (8,4)