Rails rmagick error Ubuntu c9.io - rmagick

Question

I've been looking around on other rmagick threads for a good solution. Nothing has worked so far.
I'm working on a rails project on c9 IDE. I managed to successfully install imagemagick via the 'sudo apt get install imagemagick' command.
However when I try to run 'gem install rmagick' I get the following error
Building native extensions. This could take a while...
ERROR: Error installing rmagick:
ERROR: Failed to build gem native extension.
current directory: /usr/local/rvm/gems/ruby-2.3.0/gems/rmagick-2.15.4/ext/RMagick
/usr/local/rvm/rubies/ruby-2.3.0/bin/ruby -r ./siteconf20160608-3911-1hut05d.rb extconf.rb
checking for gcc... yes
checking for Magick-config... no
checking for pkg-config... yes
Package MagickCore was not found in the pkg-config search path.
Perhaps you should add the directory containing `MagickCore.pc' to the PKG_CONFIG_PATH environment variable
No package 'MagickCore' found checking for outdated ImageMagick version (<= 6.4.9)... *** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary libraries and/or headers. Check the mkmf.log file for more details. You may need configuration options.
Provided configuration options:
--with-opt-dir
--without-opt-dir
--with-opt-include
--without-opt-include=${opt-dir}/include
--with-opt-lib
--without-opt-lib=${opt-dir}/lib
--with-make-prog
--without-make-prog
--srcdir=.
--curdir
--ruby=/usr/local/rvm/rubies/ruby-2.3.0/bin/$(RUBY_BASE_NAME)
To see why this extension failed to compile, please check the mkmf.log which can be found here:
/usr/local/rvm/gems/ruby-2.3.0/extensions/x86_64-linux/2.3.0/rmagick-2.15.4/mkmf.log extconf failed, exit code 1
Gem files will remain installed in /usr/local/rvm/gems/ruby 2.3.0/gems/rmagick-2.15.4 for inspection.
Results logged to /usr/local/rvm/gems/ruby-2.3.0/extensions/x86_64-linux/2.3.0/rmagick-2.15.4/gem_make.out

Answer 1

Try this (working for rmagick 3.0.0):
brew install imagemagick#6
brew link --force imagemagick#6
gem install rmagick