To factor the expression \(10c - 25\) by dividing out the greatest common factor (GCF), we first need to identify the GCF of the terms in the expression.
The coefficients are 10 and -25. The GCF of 10 and 25 is 5.
Next, we can factor out the GCF from the entire expression:
\[ 10c - 25 = 5(2c - 5) \]
So, the factored form of the expression is:
\[ 5(2c - 5) \]