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If x^3 + 3x^2 – 10x = 0, indicate all the possible
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12 Jun 2017, 14:36
12 Jun 2017, 14:36
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Question Stats:
52% (01:31) correct
47% (01:13) wrong based on 229 sessions
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If \(x^3\) + \(3x^2\) – 10x = 0, indicate all the possible values for the sum of any two solutions for x.
Indicate all that apply.
A) -10
B) -5
C) -3
D) -2
E) 0
F) 2
G) 3
Re: If x^3 + 3x^2 – 10x = 0, indicate all the possible
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12 Jun 2017, 19:34
12 Jun 2017, 19:34
1
Here is what did on this question ->
x^3+3x^2-10x=0
x(x^2+3x-10)=0
One solution is x=0
Next ->
x^2+3x-10=0
x^2+5x-2x-10=0
x(x+5)-2(x+5)=0
x=2 or x=-5
Hence the solutions are => x=0,2,-5
Possible sums => -5,2,-3
Hence B,C,F
x^3+3x^2-10x=0
x(x^2+3x-10)=0
One solution is x=0
Next ->
x^2+3x-10=0
x^2+5x-2x-10=0
x(x+5)-2(x+5)=0
x=2 or x=-5
Hence the solutions are => x=0,2,-5
Possible sums => -5,2,-3
Hence B,C,F
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Re: If x^3 + 3x^2 – 10x = 0, indicate all the possible
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14 Jun 2017, 06:10
14 Jun 2017, 06:10
3
Carcass wrote:
If \(x^3\) + \(3x^2\) – 10x = 0, indicate all the possible values for the sum of any two solutions for x.
Indicate all that apply.
A) -10
B) -5
C) -3
D) -2
E) 0
F) 2
G) 3
Show: :: OA
B, C,F
Given: x³ + 3x² - 10x = 0
Factor out x to get: x(x² + 3x - 10) = 0
Factor quadratic to get: x(x + 5)(x - 2) = 0
So, x = 0, or x + 5 = 0, or x - 2 = 0
If x + 5 = 0, then x = -5
If x - 2 = 0, then x = 2
The 3 solutions are: x = 0, x = -5, and x = 2
Adding all 3 possible pairs of solutions, we get the following sums: -5, 2, and -3
Answers:
Show: ::
B, C, F
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