Answer:
Option C.
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Explanation:
we know that
If a system of two linear equations has an infinite number of solutions, then both equations must be identical
The given equation is
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Verify each case
Option A. we have
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apply distributive property

Compare with the given equation

Option B. we have
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remove the parenthesis
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Compare with the given equation
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Option C. we have
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apply distributive property
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Compare with the given equation

therefore
This equation with the given equation form a system that has an infinite number of solutions
Option D. we have
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Compare with the given equation
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