High School

Which choice is equivalent to the expression below? √9x - √4x + 4√x?
A. 3√2x + 4

Answer :

To determine which choice is equivalent to the expression [tex]\sqrt{9x} - \sqrt{4x} + 4\sqrt{x}[/tex], let's simplify each of the square roots this expression contains.

  1. Simplify [tex]\sqrt{9x}[/tex]:

    • [tex]\sqrt{9x} = \sqrt{9} \times \sqrt{x} = 3\sqrt{x}[/tex].
  2. Simplify [tex]\sqrt{4x}[/tex]:

    • [tex]\sqrt{4x} = \sqrt{4} \times \sqrt{x} = 2\sqrt{x}[/tex].

Now, substitute these simplified results back into the original expression:

[tex]3\sqrt{x} - 2\sqrt{x} + 4\sqrt{x}[/tex]

Combine like terms:

  • [tex](3\sqrt{x} - 2\sqrt{x}) + 4\sqrt{x} = 1\sqrt{x} + 4\sqrt{x} = 5\sqrt{x}[/tex].

Therefore, the expression [tex]\sqrt{9x} - \sqrt{4x} + 4\sqrt{x}[/tex] simplifies to [tex]5\sqrt{x}[/tex].

Upon reviewing the provided choices, it appears there is an error as none of the given options match this simplified result.

If option A is suggested as [tex]3\sqrt{2x} + 4[/tex], cross-checking against the correct simplified form shows they are not equivalent. This suggests the option provided does not represent a correct simplification.