2
algebraFor what value of does the system have no solution?
A
B
C
D
Any value except 20
Correct Answer: D
Choice D is the correct answer. For no solution, we need parallel lines (proportional coefficients but different constants).
Step 1: Notice the second equation's coefficients are double the first:
Step 2: Analysis:
- If : equations are identical → infinitely many solutions
- If : equations have same left side but different right side → parallel lines → no solution
Conclusion: No solution for any value except 20.
💡 Strategic Tip: Parallel lines occur when left sides are proportional but right sides aren't.
Choice A is incorrect because gives infinitely many solutions, not no solution.
Choice B is incorrect because while gives no solution, it's not the only such value.
Choice C is incorrect because while gives no solution, it's not the only such value.