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Solve the equation.

3x^3 - 9x^2 = 30x

Please explain your answer in steps so I can understand what to do, thanks a mil in advance.

User DJ Martin
by
7.5k points

1 Answer

1 vote

Answer:

-2, 0, and 5

Explanation:

3x³ − 9x² = 30x

Move everything to one side:

3x³ − 9x² − 30x = 0

Factor out the greatest common factor (in this case, 3x):

3x (x² − 3x − 10) = 0

Factor the quadratic:

3x (x − 5) (x + 2) = 0

Set each factor to 0 and solve:

3x = 0 → x = 0

x − 5 = 0 → x = 5

x + 2 = 0 → x = -2

Possible solutions are x = -2, x = 0, and x = 5.

User Ajlane
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8.8k points