If is the solution to the given system of equations, what is the value of y ?

Question

Accepted Answer

Choice B is correct. Substituting 20 for in the second equation in the system yields , or . Subtracting 40 from both sides of this equation yields . Dividing both sides of this equation by 3 yields . Choice A is incorrect. If , then since . However, substituting 10 for both x and y in the second equation yields , which is a false statement. Choice C is incorrect. If , then since . However, substituting these values for x and y in the second equation yields , which is a false statement. Choice D is incorrect. If , then since . However, substituting these values for x and y in the second equation yields , which is a false statement.

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