Question

Which of the following is a linear function?

Answer 1

$\boxed{ \textbf{ \huge{Answer: A}}}$

A linear function has 1 as the highest power of the variable.

A. f(x) = 2 - 7x

here, the highest power of the variable x is 1.
Hence it is a LINEAR function.
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B. f(x) = 2 + x + x^2

here, the highest power of the variable x is 2.
Hence it is NOT a linear function.
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$c.f(x) = \sqrt{2 + 7x}$
here, the highest power of the variable x is 1/2.
Hence it is NOT a linear function.
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