[Freeswitch-users] No package speex-devel available.

I am attempting to build Freeswitch, using these instructions: https://freeswitch.org/confluence/display/FREESWITCH/CentOS+6 How do I resolve these two "yum install" errors? No package speex-devel available. No package libedit-devel available. And even though "speex" is installed (yum: Package speex-1.2-0.19.rc1.el7.x86_64 already installed and latest version), I am getting this build error: checking for speex >= 1.2rc1 speexdsp >= 1.2rc1... Package speex was not found in the pkg-config search path. What is the workaround for this error? Thanks!