Install VBoxGuestAdditions on Oracle Linux 7

certainly have you found that the resolution is very bad.
only install Oracle Linux 7 on VirtualBox is not sufficient, we need VBoxGuestAdditions for our System
let us, we can it make better. first we download the VBoxGuestAdditions_4.3.18.iso from:
http://download.virtualbox.org/virtualbox/4.3.18/
then start your Orcle VM Virtual Machine
click on the Button 'Storage' and add a new 'Controller: IDE'

3- now you can start your Oracle Linux 7
4- on Line command execute following:
[akh@localhost VBOXADDITIONS_4.3.18_96516]$ su
Password:
[root@localhost VBOXADDITIONS_4.3.18_96516]# ./VBoxLinuxAdditions.run
Verifying archive integrity... All good.
Uncompressing VirtualBox 4.3.18 Guest Additions for Linux............
VirtualBox Guest Additions installer
Copying additional installer modules ...
Installing additional modules ...
Removing existing VirtualBox non-DKMS kernel modules [ OK ]
Building the VirtualBox Guest Additions kernel modules
Building the main Guest Additions module [ OK ]
Building the shared folder support module [ OK ]
Building the OpenGL support module [ OK ]
Doing non-kernel setup of the Guest Additions [ OK ]
Starting the VirtualBox Guest Additions [ OK ]
Installing the Window System drivers
Installing X.Org Server 1.15 modules [ OK ]
Setting up the Window System to use the Guest Additions [ OK ]
You may need to restart the hal service and the Window System (or just restart
the guest system) to enable the Guest Additions.
Installing graphics libraries and desktop services componen[ OK ]
[root@localhost VBOXADDITIONS_4.3.18_96516]#
-- start your Windows System, your Oracle Linux7 resolution is now optimal

continue withe: Install Oracle-XE on Oracle linux-7