Find the value of two numbers if their sum is 12 and their difference is 4

x + y = 12
Equation 2: Difference:
x - y = 4
Solution:
x + y = 12
x - y = 4
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Add the two equations together:
2x = 16
Divide both sides by 2:
x = 8
Solve for y:
Use equation 1 substituting for x:
x + y = 12
8 + y = 12
Subtract 8 from both sides:
y = 4
Answer:
one number is 8 and the other number is 4.
8 + 4 = 12
8 - 4 = 4