(8z+4)(8z-4)
Apply the distributive property.
8z(8z-4)+4(8z-4)
Apply the distributive property.
8z(8z)+8z⋅-4+4(8z-4)
Apply the distributive property.
8z(8z)+8z⋅-4+4(8z)+4⋅-4
8z(8z)+8z⋅-4+4(8z)+4⋅-4
Combine the opposite terms in 8z(8z)+8z⋅-4+4(8z)+4⋅-4.
Reorder the factors in the terms 8z⋅-4 and 4(8z).
8z(8z)-4⋅8z+4⋅8z+4⋅-4
Add -4⋅8z and 4⋅8z.
8z(8z)+0+4⋅-4
Add 8z(8z) and 0.
8z(8z)+4⋅-4
8z(8z)+4⋅-4
Simplify each term.
Multiply z by z.
8⋅8z2+4⋅-4
Multiply 8 by 8.
64z2+4⋅-4
Multiply 4 by -4.
64z2-16
64z2-16
64z2-16
Simplify (8z+4)(8z-4)