Right-to-Left Support
The RadCheckBox fully supports right-to-left (RTL) language locales (Figure 1). In order to turn on the RTL support, you should set dir=rtl to the html or body element or at least to its parent element (Figure 1). You can also use the direction:rtl CSS property.
<div style="direction: rtl;">
<telerik:RadCheckBox ID="RadCheckBox1" runat="server" Text="موافق" Checked="true">
</telerik:RadCheckBox>
</div>