If x is a number such that x2 + 2x - 24 = 0 and x2 + 5x - 6 = 0, then

Question

If x is a number such that x^2 + 2x - 24 = 0 and x^2 + 5x - 6 = 0, then x =

A. -6
B. -4
C. -3
D. 3
E. 6

AmoyV · Answer

(x+6)(x-4)=0...x=-6 OR 4
(x+6)(x-1)=0...c=-6 OR 1

Answer: A

Harley1980 · Answer

for first equation 
x + x = -2
x * x = -24 
so x = -6 or 4

for second equation 
x + x = -5
x * x = -6 
so x = -6 or 1

we have one common answer for x: this is -6
and answer is A

gmatgrl · Answer

x^2 + 2x - 24 = 0 
x^2 + 5x - 6 = 0

Subtracting the two equations,
-3x = 18
So, x = -6

jugglerG2 · Answer

Hi  Bunuel ,

I solved this question by equating the two equations, can you please suggest whether anything is wrong in this approach, or if I should add some steps to make this approach foolproof?

x^2 + 2x - 24  =  x^2 + 5x - 6 
=>  3x = -18 
=>  x = -6

IMO correct answer is A.

Lucky2783 · Answer

X2 + 5x - 6 = 0, then x =-6, 1

Since 1 is not in option , -6 is answer.
answer a

earnit · Answer

1st method:  
Equate both the equations: 
 x^2 + 2x - 24 = x^2 + 5x - 6 
 3x = -18 
 x = -6 
Satisfies both equations.

Answer:A

Longer method/Alternate:

Solve each equation:  x^2 + 2x - 24 = 0 
 x = 4,-6

x^2 + 5x - 6 = 0, 
 x = 1,-6

Clearly x = -6 after taking the intersection and this values satisfies both equations. 
 Answer:A

PareshGmat · Answer

Answer = A = -6

x^2 + 2x - 24 = x^2 + 5x - 6 = 0

-3x = 18

x = -6

Had only one equation been given, "x" would had derived 2 values. However in this case, two equations are given

So, this will yield "ONLY ONE ANSWER" for x because value of "x" has to SATISFY both equations

KS15 · Answer

Answer=A
x^2+2x-24=x^2+6x-4x-24=(x+6)(x-4)=0
x=-6 or x=4
and x^2+5x-6=x^2+6x-x-6=0
(x+6)(x-1)=0
x=-6 or x=1
Using both, x=-6

Bunuel · Answer

MAGOOSH OFFICIAL SOLUTION:

bumpbot · Answer

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If x is a number such that x2 + 2x - 24 = 0 and x2 + 5x - 6 = 0, then

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