One of the solutions to x2 − 2x − 15 = 0 is x = −3. What is the other solution? x = −5 x = −1 x = 1 x = 5

Question

One of the solutions to x2 − 2x − 15 = 0 is x = −3. What is the other solution?

x = −5
x = −1
x = 1
x = 5

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Gerda 3 years 2021-09-05T11:40:53+00:00 1 Answers 0 views 0

Answers ( )

  1. Edana
    0
    2021-09-05T11:42:03+00:00
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    Answer: x = 5

    Step-by-step explanation:

    x² – 2x – 15 = 0

    x² + 3x – 5x – 15 = 0

    x(x + 3) – 5(x + 3) = 0

    Therefore, x + 3 = 0

    x = 0 – 3 = -3

    Also, x – 5 = 0

    x = 0 + 5 = 5

    Therefore, the solutions to x² – 2x – 15 = 0 is x = -3 and x = 5. Therefore, the correct option is D.

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