What is the value of xy ? (1) y – 1 = x (2) x^2 + x – 6 = 0

Question

What is the value of xy ?
 
(1) y – 1 = x 
(2) x^2 + x – 6 = 0

kumarparitosh123 · Answer

It's a C.

Statement 1: Give no additional information.. not sufficient.

Statement 2: x= 2 and -3.
Not sufficient.
Statement 1 and 2 together:

Sufficient. It. Gives a value of 6 when solved.

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tatz · Answer

Statement 1 : y-1=x, y=x+1, xy=x(x+1)-- no solution
Statement 2: Solve the quadratic equation and we get x= 2, -3
If x=2, y=3 (With help from Statement 1), then xy =3x2= 6
If x=-3, y=-2 (With help from Statement 1), then xy =-3 x -2= 6.
Answer is C- BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked.

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What is the value of xy ? (1) y – 1 = x (2) x^2 + x – 6 = 0

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