Delete a DNS Record

To delete a resource record using a command line

1. Open a command prompt. To open an elevated Command Prompt window, click Start, point to All Programs, click Accessories, right-click Command Prompt, and then click Run as administrator.
2. Type the following command, and then press ENTER:
   dnscmd <ServerName> /RecordDelete <ZoneName> <NodeName> <RRType> <RRData> [/f]

dnscmd server_name /RecordDelete zone_name host_name1 A 7.7.7.90 /f
dnscmd server_name /RecordDelete zone_name host_name2 A 7.7.7.91 /f
dnscmd server_name /RecordDelete zone_name host_name3 A 7.7.7.92 /f
dnscmd server_name /RecordDelete zone_name host_name4 A 7.7.7.93 /f
dnscmd server_name /RecordDelete zone_name host_name5 A 7.7.7.94 /f
dnscmd server_name /RecordDelete zone_name host_name6 A 7.7.7.95 /f
dnscmd server_name /RecordDelete zone_name host_name7 A 7.7.7.96 /f
dnscmd server_name /RecordDelete zone_name host_name8 A 7.7.7.97 /f

https://technet.microsoft.com/en-us/library/cc901585(v=ws.10).aspx