The sum of two numbers is 80 and their difference is 20. What are the two numbers?
The sum of two numbers is 80 and their difference is 20. What are the two numbers?
Explanation
Let's start by calling the two numbers we are looking for x and y.
x + y = 80
x - y = 20
x - y = 20
x = 20 + y
x + y = 80
20 + y + y = 80
20 + 2y = 80
2y = 60
y = 30
x + y = 80
x + 30 = 80
X = 50
Sum: 50 + 30 = 80
Difference: 50 - 30 = 20