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Never factor again — graph both and look

Equivalent means the same graph, so graph the ugly one and see which choice lands on top.

1:59 · Equivalent Expressions

Episode 7: Never factor again — graph both and look

Worked in this video

(x² − 4)/(x² + x − 6) · (x² + 5x + 6)/(x² − x − 2), for x ≠ −3, −1, 2

Which expression is equivalent? (A) (x + 2)²/((x − 2)(x + 1)) (B) (x − 2)²/((x + 2)(x + 1)) (C) (x + 2)/(x + 1) (D) (x + 2)(x + 3)/((x − 2)(x + 1))

Equivalent means the same graph. Type the expression into Desmos as y = exactly as it is printed, then type the answer choices one at a time. A wrong choice draws a different curve; the equivalent one lands exactly on top of the original. On paper this is factoring all four quadratics, cancelling in exactly the right places and rebuilding what is left, and one bad factor ruins it.

Answer: (x + 2)²/((x − 2)(x + 1)) — answer A

    Never factor again — graph both and look — The Desmos Series | UnlimitedTests