What is the LCD?? please help

This is the problem:

z^2-64, 2z+16, z

and it says find the LCD...would it be 2z^2+16 then? you combine whatever is biggest together right.

The LCD = 1
The LCM = 2z(z-8)(z+8)

Okay a little work needs to be done here first.

Factor the first two expressions we get:

(z-8)(z+8) [difference of squares)
2(z+8)
z

Now to find the LCD, find what is the least needed for all three terms to be the same, well they all need a (z-8) a (z+8) a z and a 2 so your LCD is:
2z(z-8)(z+8)

I think you mean the 'least common multiple !' ...there are no fractions in your presentation !

factor to find prime factors...

z^2 - 64 = (z + 8)(z - 8)

2z + 16 = 2(z + 8)

z = z

the LCM is: 2 * z * (z + 8) * (z - 8)

@ß

The Lowest Common Multiple is 1.

Lowest Common Denominator

Lowest Common Denominator