Including Open Graph meta tags and Twitter card tags for SEO

Question

I have used these tags before to share some content for user to preview on Facebook or Twitter before they actually go into the shared link/video. But when I was asked to include these tags only for SEO I had this doubt which I can split into two parts

part 1: Let us assume these tags are included in the head tag of HTML doc. But there are no like, tweet or share links in the page.
a) Will these tags then help Google to search this page (assuming the page already has title and description meta tag)?
b) Will these tags help search used within Facebook and Twitter?

part 2: Let us assume these tags are included in the head tag of HTML doc and also there are like or share links in the page.
c) Will these tags then help Google, Facebook and Twitter to search this page since there will be lot of clicks happening through these like, tweet and share links.

Answer 1

Facebook only searches content inside Facebook and Twitter only searches content inside Twitter. Unlike Google and Bing, Twitter and Facebook are not search engines. Facebook uses Bing results if the user selects "web results" in the menu.

Open Graph and Twitter card are used exclusively to display content within social networks. Open Graph data is also used by Google Plus (another social network) to display a small snippet of the page when a user shares a link to your page.

Google search uses content from the "classic" <title> tag and sometimes from the <meta description> tag.