Android - Clearing Navigation Backstack

I have 4 pages.

From page_1 > page_2 > page_3 > page_4.

Once the user reaches page_3 and clicks a button, it navigates to page_4. Once the button is clicked, I want to clear all the navigation history so when the user goes back on page_4, the app quits rather than going back to page_3.

I've tried:

    Intent intent = new Intent(this, page_4.class);
    intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK);
    startActivity(intent);
    finish();

But nothing happens. I can still go back to page_3, page_2 etc. How do I make it so that when the user clicks on the button on page_3, he goes to page_4 and from page_4 there shouldn't be any navigation history?