1) 

Take square roots of both sides, but don't 
forget ± on the right side:

 = ±

 = ±

Add -16 to both sides:

±

Using the +





Using the -






2)

Sorry, you mistyped that one as it shouldn't 
have two equal signs, and especially since
16 does not equal 36.  Repost it as it should 
be and we'll help you with it.


3) 

You didn't say what you are to do with this
equation, so I'll arbitrarily assume the 
instructions were to solve for z.  If that
was not what you were told to do with the 
equation, then post again, this time giving
the instructions.


Take square roots of both sides, but don't 
forget ± on the right side:

 = ±

 = ±

Add s to both sides:

±

Using the +



Using the -



Edwin