9514 1404 393
Answer:
9 -36z²
Step-by-step explanation:
The form of the given product matches the form of the "special product" ...
(a -b)(a +b) = a² -b² . . . . . . . factoring of the difference of squares
You have a=3, b=6z, so the product is ...
(3)² -(6z)² = 9 -36z²
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Additional comment
If you like, you can work this out using the distributive property.
(3 -6z)(3 +6z) = 3(3 +6z) -6z(3 +6z) . . . . use the distributive property
= 9 +18z -18z -36z² . . . . . . . use the distributive property again
= 9 -36z² . . . . . . . . . collect terms
