Engineering Board Exam Reviewer · Cramer's Rule and Linear Systems · easy

How many solutions does the system x+y=2, 2x+2y=5 have?

1. No solution
2. Exactly one solution
3. Infinitely many solutions
4. Exactly two solutions

Answer

A. No solution

Solution

Doubling the first equation gives 2x+2y=4, which contradicts 2x+2y=5. The system is inconsistent, so there is no solution.

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