a number divided by 25 leaves remainder 9 . what is that number?
x / 25 = 9 -> x = 225
A number divided by 25 leaves remainder 9 . what is that number?
\(x\equiv 9 \pmod {25} \\ \text{or}\\ x-9 = z\cdot 25\\ x = 9+z\cdot 25 \qquad z \in Z\\\\ \mathbf{ x = \dots,-41, -16, 9, 34, 59, 84,\dots }\)