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If 25x^2−5x−10=100, then what is the sum of all the possible values
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04 May 2016, 11:08
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80% (02:20) correct 20% (02:27) wrong based on 262 sessions
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If \(25x^2−5x−10=100\), then what is the sum of all the possible values of x? A. 10 B. 8 C. 2 D. 4 E. 8
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Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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Updated on: 04 May 2016, 12:09
It is 10. expression = 4 exp = +4 => on solving x=7 and 2 exp = 4 => on solving x = 3 and 2 7  2 + 2 + 3 = 10 updated *roots for 2nd exp are wrong, that should be 6 or 1 instead of +3 or 2* 72+61 = 10 is correct oa pls
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Originally posted by snorkeler on 04 May 2016, 11:42.
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Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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04 May 2016, 11:56
[quote="Bunuel"]If \(25x^2−5x−10=100\), then what is the sum of all the possible values of x?
A. 10 B. 8 C. 2 D. 4 E. 8
Answer is A
x^25x10=4 will give you x=2 and 7 (x^25x10)= 4 will give you x =1 and 6 2+7+1+6=10



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If 25x^2−5x−10=100, then what is the sum of all the possible values
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04 May 2016, 13:49
x²  5x  10 = 4 => x²  5x  14 = 0 => (x  7) (x + 2) = 0 => x = 7 or x = 2 x²  5x  10 =  4 => x²  5x  6 = 0 => (x + 1) (x 6) = 0 => x = 6 or x = 1
7 2 + 6  1 = 10



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Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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31 Dec 2018, 04:51
Bunuel wrote: If \(25x^2−5x−10=100\), then what is the sum of all the possible values of x?
A. 10 B. 8 C. 2 D. 4 E. 8 \(25x^2−5x−10=100\) x^2−5x−10=4 x^2−5x−10=4 x=7 & 2 or say (x^2−5x−10)=4 x=3,+2 sum = 72+2+3 = 10 IMO A
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Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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02 Jan 2019, 05:18
Solution Given:• \(25x^2  5x  10 = 100\) To find:• The sum of all the possible values of x Approach and Working: \(x^2  5x  10 = \frac{100}{25}= 4\) • This implies, \(x^2  5x – 10 = 4\) or \(x^2  5x – 10 = 4\)
o \(x^2  5x – 14 = 0\), implies, x = 7 or 2 o \(x^2  5x – 6 = 0\), implies, x = 6 or 1 Therefore, sum of all possible values of x = 7 – 2 + 6 – 1 = 10 Hence, the correct answer is Option A Answer: A
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Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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01 Feb 2019, 23:41
Bunuel wrote: If \(25x^2−5x−10=100\), then what is the sum of all the possible values of x?
A. 10 B. 8 C. 2 D. 4 E. 8 Just solve both the quadratic expressions formed when we open the modulus \(x^2  5x 14 = 0\), will give x as 2 and 7 \(x^2  5x + 6 = 0\), will give x as 2 and 3 Add all the values of x to get 10 A
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Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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14 Feb 2019, 23:49
for the equation ax^2 + bx + c = 0 ,the sum of roots is given by (b/a)
now acc. to ques: x^2−5x−10=4
=> x^2−5x−10= 4 ...... eq(1) and x^2−5x−10= 4 ...... eq(2)
now from eq (1) and eq (2)
r1 + r2 = (5/1)= 5 r3 + r4 = (5/1)= 5
therefore , r1 + r2 + r3 + r4= 10



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Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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15 Feb 2019, 00:33
Bunuel wrote: If \(25x^2−5x−10=100\), then what is the sum of all the possible values of x?
A. 10 B. 8 C. 2 D. 4 E. 8 \(25x^2−5x−10=100\) i.e. \(x^2−5x−10=4\) i.e. \(x^2−5x−10=4\) or i.e. \(x^2−5x−10=4\) i.e. \(x^2−5x−14=0\) or i.e. \(x^2−5x−6=0\) i.e. \(x^2−7x+2x−14=0\) or i.e. \(x^2−6x+x−6=0\) i.e. \((x+2)*(x7)=0\) or i.e. \((x−6)*(x+1)=0\) i.e. x = 2, 7, 6, 1 Aum of all values of x = 10 Answer: Option A
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Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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29 Mar 2019, 11:43
hello folks!
if we apply the 'open up modulus' method, and find the solutions from both equations (i.e. 6, 1, 7, 2), do we need to test each one solution in the formula and check if they're correct?
or can we just take the solutions and sum them up without checking?
thanks!




Re: If 25x^2−5x−10=100, then what is the sum of all the possible values
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29 Mar 2019, 11:43






