title: Could not set unknown property 'useAndroidX' for object of type com.android.build.gradle.internal.dsl.BaseAppModuleExtension
body: <p>I want to add a library that i've found on github but it required androidx.I found out that i should put these:</p>
  
  <pre><code>android.useAndroidX=true
  android.enableJetifier=true
  </code></pre>
  
  <p>here</p>
  
  <pre><code>defaultConfig {
      applicationId "com.kolydas.greeksinbrno"
      minSdkVersion 19
      targetSdkVersion 28
      versionCode 1
      versionName "1.0"
      testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
      android.useAndroidX=true
      android.enableJetifier=true
  
  }
  </code></pre>
  
  <p>But i got this error</p>
  
  <blockquote>
    <p>Could not set unknown property 'useAndroidX' for object of type com.android.build.gradle.internal.dsl.BaseAppModuleExtension.</p>
  </blockquote>