Answer:
Step 1: Distributive Property
Step 2: Distributive Property
Step 3: Commutative Property
Explanation:
Step 1: This is distributing the (x + 4y + z) into the (x - 7y), so each term in the prior expression is multiplied by (x - 7y). Hence, Distributive Property.
Step 2: This is doing the same thing but to each individual term. The x in the first term is multiplied by each term in the (x - 7y), the 4y in the second term is multiplied by each term in the (x - 7y), and the same for z. Hence, Distributive Property.
Step 3: This is reordering the variables in the terms. For example, 4yx is changed to 4xy, and that is possible because of the Commutative Property. zx is also reordered into a xz and 7zy into a 7yz.
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