I can't find a listing for a Blazer in 2010 so I looked up a Colorado. That truck uses a "captive" rotor design which makes the job a lot more complicated than necessary. You have to unbolt the wheel bearing assembly, remove it, then unbolt the rotor from behind.
When you put the rotor back on, be sure there is no rust, scale, or other debris stuck between the parts to cause a wobble and pedal pulsation. Also, if you have a four-wheel-drive model, be absolutely certain the axle nut is torqued to specs before any vehicle weight is placed on the wheel bearing. Doing so with the nut not sufficiently tightened will lead to the bearing becoming very noisy.