2 numbers that are equal have a sum of 60

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2 numbers that are equal have a sum of 60

Let's choose 2 arbitrary variables for the 2 numbers
x, y

Were given 2 equations:

1. x = y <-- Because we have the phrase that are equal
2. x + y = 60

Because x = y in equation (1), we can substitute equation (1) into equation (2) for x:
y + y = 60

Add like terms to get:
2y = 60

Divide each side by 2:
2y/2 = 60/2

Cancel the 2's and we get:
y = 30

Since x = y, x = y = 30
x = 30