title: preg_match for specific numbers
body: <p>I'm trying to preg_match numbers which can be in any of these formats:</p>
  
  <p>1) 81113333 or 91113333 (8-digit without any space in between. must start with 8 or 9)</p>
  
  <p>2) 8111 3333 or 9111 3333 (8-digit with a space in between. must start with 8 or 9)</p>
  
  <p>3) 8111-3333 or 9111-3333 (8-digit with a hyphen in between. must start with 8 or 9)</p>