I am thinking of a number.i multiply it by 5 and add 139. I get the same number if I multiply by 13

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I am thinking of a number.i multiply it by 5 and add 139. I get the same number if I multiply by 13 and subtract 13.What is my number?

Take a number (n):

The first operation is multiply 5 times n, and then add 39:
5n + 139

The second operation is multiply 13 times n and subtract 13:
13n - 13

Set both operations equal to each other since they result in the same number
5n + 139 = 13n - 13

Type this equation into our search engine and we get:
n = 19