title: Error:Failed to resolve: com.google.firebase:firebase-core:11.0.0
body: <p>I am trying to implement Authenticate with Firebase on Android using a Phone Number  and its second step is to  add the dependency for Firebase Authentication to your app-level build.gradle file:</p>
  
  <pre><code>compile 'com.google.firebase:firebase-auth:11.0.0'
  &lt;br&gt;after adding it , I try to sync project with Gradle Files
  and it showing error&lt;br&gt;Error:Failed to resolve: com.google.firebase:firebase-core:11.0.0
  &lt;a href="openFile:/project/Mobileveridacetion/app/build.gradle"&gt;Open File&lt;/a&gt;&lt;br&gt;&lt;a href="open.dependency.in.project.structure"&gt;Show in Project Structure dialog&lt;/a&gt;&lt;br&gt;Error:(26, 13) Failed to resolve: com.google.firebase:firebase-auth:11.0.0
  &lt;a href="openFile:/project/Mobileveridacetion/app/build.gradle"&gt;Show in File&lt;/a&gt;&lt;br&gt;&lt;a href="open.dependency.in.project.structure"&gt;Show in Project Structure dialog&lt;/a&gt;
  </code></pre>