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Comment on Number of Solutions to a System
@1.14 Can we just leave one
When you multiply/divide both
When you multiply/divide both sides of an equation by some value, you are creating an EQUIVALENT equation. For example, the equation x + y = 3 is EQUIVALENT to the equation 2x + 2y = 6
So, to answer your question, you need not multiply both EQUATIONS by 2.
Beautifully explained!
Thanks Swatato!
Thanks Swatato!
So is the answer a+b = -2?
Exactly.
Exactly.
When we solve each equation we get:
a = -6 OR a = 4
b = -6 OR b = 4
Since a ≠ b, we know that one solution is -6 and the other solution is 4
So, a + b must equal -2
Cheers,
Brent
Hi, for this question link
the answer should be A, as equation 1 and 2 are not equivalent?
Question link: https:/
Question link: https://gmatclub.com/forum/the-system-of-equations-has-how-many-solution...
You're absolutely right. For some reason, I was solving a completely different system of equations.
I have edited my solution accordingly.
Thanks for the heads up!
Question link: https:/
Question link: https://gmatclub.com/forum/the-system-of-equations-has-how-many-solution...
You're absolutely right. For some reason, I was solving a completely different system of equations.
I have edited my solution accordingly.
Thanks for the heads up!