Example

Multiplying (2x+7)(2x7)(2x + 7)(2x - 7) Using the Product of Conjugates Pattern

Apply the Product of Conjugates Pattern to multiply (2x+7)(2x7)(2x + 7)(2x - 7). Confirm the binomials are conjugates: both share the same first term 2x2x and the same last term 77, with one using addition and the other subtraction. Use the formula (a+b)(ab)=a2b2(a + b)(a - b) = a^2 - b^2, where a=2xa = 2x and b=7b = 7.

Step 1 — Square the first term, 2x2x: (2x)2=4x2(2x)^2 = 4x^2. Both the coefficient and the variable must be squared separately: 22=42^2 = 4 and x2=x2x^2 = x^2. Step 2 — Square the last term, 77: 72=497^2 = 49. Step 3 — Write the difference of squares: (2x+7)(2x7)=4x249(2x + 7)(2x - 7) = 4x^2 - 49

The product is 4x2494x^2 - 49.

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Updated 2026-04-29

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