卡在這題?用 AI 解開它
algebra · worked example

Solve x² - 16 = (x - 4)(x + 4)

Method: 平方差. Verified step-by-step solution with our free AI math solver.
Problem

x2−16x^2 - 16

Step-by-step solution

  1. 將 x2−16x^2 - 16 視為 a2−b2a^2 - b^2,其中 a=xa = x、b=4b = 4(因為 42=164^2 = 16)。

  2. 套用恆等式 a2−b2=(a−b)(a+b)a^2 - b^2 = (a-b)(a+b)。

  3. 結果:(x−4)(x+4)(x - 4)(x + 4)。

Answer

(x−4)(x+4)(x - 4)(x + 4)

Want to solve a different problem? Open the factoring solver →