(a+b)(a-b)=a^2-b^2

(3p + 1)(3p - 1)= 9p^2-1

This is everytime less than 9p^2 as 1 is deducted from it irrespective of it's value. This also hold good even if the number is a fraction or some integer.

Explanation

Evaluate the relationship between the quantities by plugging in values for p: Try p = 2.

Quantity A is 7 × 5 = 35, and Quantity B is 9 × 4 = 36; Quantity B is greater, so eliminate choices (A) and (C). Any value gives the same outcome, so select answer choice (B). Algebraically, you could either FOIL Quantity A or recognize the common quadratics—either way, Quantity A simplifies to 9p2 – 1, which is always exactly 1 less than Quantity B.
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