Sure thing, let's get straight to it. We start with 809 and we're going to multiply it by 5, which means adding 809 to itself 5 times.
Step 1: 0 + 809 = 809
Step 2: 809 + 809 = 1618
Step 3: 1618 + 809 = 2427
Step 4: 2427 + 809 = 3236
Step 5: 3236 + 809 = 4045

So, 809*5 = 4045