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If s and t are constants and x2 + sx + 8 factors into (x + 1)(x + t),
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28 Feb 2022, 04:00
28 Feb 2022, 04:00
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Question Stats:
94% (01:01) correct
5% (00:42) wrong based on 19 sessions
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If s and t are constants and \(x^2 + sx + 8\) factors into \((x + 1)(x + t)\), what is the value of \(s\)?
(A) 1
(B) 2
(C) 4
(D) 8
(E) 9
(A) 1
(B) 2
(C) 4
(D) 8
(E) 9
Re: If s and t are constants and x2 + sx + 8 factors into (x + 1)(x + t),
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28 Feb 2022, 19:45
28 Feb 2022, 19:45
1
\(x^2 + sx + 8\) \(= 0\)
\(x + 1\) & \(x + s\) are factors so they will satisfy the equation.
Put \(x = -1\) in the equation.
\(1 - s + 8 = 0\)
\(s = 9\)
The equation will be: \(x^2 + 9x + 8\) \(= 0\)
The factors will be \(x + 1\) & \(x + 8\)
\(s = 9\) & \(t = 8\)
Answer E
\(x + 1\) & \(x + s\) are factors so they will satisfy the equation.
Put \(x = -1\) in the equation.
\(1 - s + 8 = 0\)
\(s = 9\)
The equation will be: \(x^2 + 9x + 8\) \(= 0\)
The factors will be \(x + 1\) & \(x + 8\)
\(s = 9\) & \(t = 8\)
Answer E
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Joined: 09 Apr 2021
Posts: 13
Given Kudos: 26
GRE 1: Q154 V157
Re: If s and t are constants and x2 + sx + 8 factors into (x + 1)(x + t),
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05 Jul 2022, 21:55
05 Jul 2022, 21:55
Hi rx10,
The solution is valid only when we consider the above equation as quadratic. How did u know that it's a quadratic equation in the first place?
The solution is valid only when we consider the above equation as quadratic. How did u know that it's a quadratic equation in the first place?
