Maps to Category 9 of the book.
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Answer posted on 10/03/2021: Correct answer choice is D.
For a system of equations to have no solution, the ratio of c cannot be same as the ratios of a and b.
The ratio of a in the two equations is 2:5. If c = 25, then the ratio of c in two equations will be 10:25 = 2:5. Hence, c cannot be 10 for the system to have no solution.