3) The sum of two numbers is 20. Their
difference is -2. What are the two numbers?
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Answer: 9, 11 (or for the picture 48 and 52)
Step-by-step explanation:
The sum of two numbers (x, y) is 20;
x+y=20
One is 2 greater than than the other;
y=x+2
Now, we can put that in for y;
x+(x+2)=20
And solve;
2x+2=20
2x=18
x=9
Now, substitute in the value of x into the second equation;
y=9+2
And we get our answer.
y=11
My explanations are bad :(