Answer:
These are instructions for finding the product of two binomials. by, means multiplied by. Say we want to find the product ( x – 3)(2x + 1). 
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step 1: Square the First Term, 
step 2: Double the Product of the 2 terms , 
step 3: Square the Last Term. So to find (x – 5)² : square x, multiply 2 times x times – 5, square (– 5)
Explanation: