How to hide a div by default when page loads with one radio button selected in angular 2 - angular2-directives

Question

This is angular component:
How to set function in component to hide div by default when page is loaded. div Should be loaded only on clicking the radio-button.
`import { Component, OnInit } from '#angular/core';
#Component({
templateUrl: './radio-test.component.html',
styleUrls: ['./radio-test.component.css']
})
export class RadioTestComponent {
private selectedLink: string="Radio1";
setradio(e: string): void
{
this.selectedLink = e;
}
isSelected(name: string): boolean
{
if (!this.selectedLink) {
return false;
} return (this.selectedLink === name);
}
}
`
In Html:
How to call function from component so that by default no div should be displayed.
<div class="jumbotron">
<div class="radio">
<label>
<input type="radio" name="gender" value="Radio" (click)="setradio('Radio1')" >
Radio 1
</label>
</div>
<div class="radio">
<label>
<input type="radio" name="gender" value="Female" (click)="setradio('Radio2')" ngModel>
Radio 2
</label>
</div>
<div *ngIf="isSelected('Radio1')" >
<div style="height:52px;width:300px;background-color: grey;">Radio button 1 is selected </div>
</div>
<div *ngIf="isSelected('Radio2')">
<div style="height:52px;width:300px;background-color: lightgrey;">Radio button 2 is selected </div>
</div>
</div>

Answer 1

app.html
<div class="jumbotron">
<div class="radio">
<label>
<input type="radio" [(ngModel)]="model.btn" name="btn" value="btn1"
[checked]="model.btn == btn1" > Radio 1
</label>
</div>
<div class="radio">
<label>
<input type="radio" [(ngModel)]="model.btn" name="btn" value="btn2"
[checked]="model.btn == btn2">
Radio 2
</label>
</div>
<div *ngIf="model.btn=='btn1'" >
<div style="height:52px;width:300px;background-color: grey;">Radio button 1
is selected </div>
</div>
<div *ngIf="model.btn=='btn2'">
<div style="height:52px;width:300px;background-color: lightgrey;">Radio
button 2 is selected </div>
</div>
</div>
app.ts
import { Component, OnInit } from '#angular/core';
#Component({
templateUrl: './radio-test.component.html',
styleUrls: ['./radio-test.component.css']
})
export class RadioTestComponent {
model:any;
constructor(){
this.model=new Button();
this.model.btn ='btn1';
}
}
class Button {
btn: string
}