The equivalent expression for the multiplication of the rationals is given as follows:
C. [tex]\sqrt{x^2 + 7x - 18}[/tex]
How we multiply two rationals?
To multiply two rationals, we keep the root and multiply the terms inside the root.
Hence, the equivalent expression is found as follows:
[tex]\sqrt{x - 2} \times \sqrt{x + 9} = \sqrt{(x - 2)(x + 9)} = \sqrt{x^2 + 7x - 18}[/tex]
Thus, option C is correct.
More can be learned about multiplication of rationals at https://brainly.com/question/21379687
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