Algebra practice question

Answer: A. −15

Infinitely many solutions means the equations are multiples of each other. The second is 3 times the first: 3(2x − 5y) = 6x − 15y and 3 × 8 = 24 ✓. So k = −15.

Why the other answers are wrong

B. 15

15 has the wrong sign; 3 × (−5) = −15.

C. −5

−5 keeps the first equation's coefficient without scaling by 3.

D. 3

3 is the scale factor, not k.

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