what is the answer to this problem

Answer:
Step-by-step explanation:
The completed problem is
[tex]5 \times 70=5\times 7 \ tens.\\5 \times 70=35 \ tens=350[/tex]
Basically, the process is only about separating tens from units, so basically "tens" represents the zero, that's why we only multiply 5 and 7 digits, and add the zero at the end. It's an easier way to multiply tens.