81. What is the value of | (x+5)/(x+7) |?
(1) x2 + 7x - 18 = 0
(2) 3x2 + 46x + 171 = 0
Hello, below is the explanation they gave but in the problem it says the absolute value of the given equation so I assumed when I solved Statement 1 it would be ok. Is it because it is 2 differnt numbers? Please explain your approach or logical thoughts
Statement (1)
x2 + 7x - 18 = 0
x = -9 and 2
For x = -9, | (x+5)/(x+7) | = 2
For x = 2, | (x+5)/(x+7) | = 7/9
Hence, NOT SUFFICIENT
Statement (2)
3x2 + 46x + 171 = 0
x = -19/3 or -9
For x = -19/3, | (x+5)/(x+7) | = 2
For x = -9, | (x+5)/(x+7) | = 2
In this question, if you assume that for different x, the value of | (x+5)/(x+7) | would be different every time you would be wrong. Be very careful with modulus.
Hence SUFFICIENT.
The correct answer is B;
statement 2 alone is sufficient.
(1) x2 + 7x - 18 = 0
(2) 3x2 + 46x + 171 = 0
Hello, below is the explanation they gave but in the problem it says the absolute value of the given equation so I assumed when I solved Statement 1 it would be ok. Is it because it is 2 differnt numbers? Please explain your approach or logical thoughts
Statement (1)
x2 + 7x - 18 = 0
x = -9 and 2
For x = -9, | (x+5)/(x+7) | = 2
For x = 2, | (x+5)/(x+7) | = 7/9
Hence, NOT SUFFICIENT
Statement (2)
3x2 + 46x + 171 = 0
x = -19/3 or -9
For x = -19/3, | (x+5)/(x+7) | = 2
For x = -9, | (x+5)/(x+7) | = 2
In this question, if you assume that for different x, the value of | (x+5)/(x+7) | would be different every time you would be wrong. Be very careful with modulus.
Hence SUFFICIENT.
The correct answer is B;
statement 2 alone is sufficient.
