Answer:
13 and 7
Explanation:
We have two unknown numbers that add up to 20 and subtract to 6. The question is asking us to find out these two hidden numbers.
Let's form two equations.
x + y = 20
and
x - y = 6
Since we have a positive y and negative y, we can use the addition method to these systems of equations.
x + y = 20
x - y = 6
+-----------------
2x = 26
Now isolate x to get x.
Divide both sides by 2 :
x = 13
Now that we have x, we can plug it into the equations.
13 + y = 20
13 - y = 20
So what number will make this true. Use the backwards method :
20 - 13 = 7
Therefore, 13 and 7 are our two numbers.