Select the rational expression that is equivalent to the given expression below.

[tex]\[
\frac{4}{a-3}
\][/tex]

A. [tex]\(\frac{x+2}{x-3} - \frac{4}{x+2}\)[/tex]

B. [tex]\(\frac{z+2}{x-3} + \frac{4}{x+2}\)[/tex]

C. [tex]\(\frac{x+2}{x-3} \cdot \frac{4}{x+2}\)[/tex]

D. [tex]\(\frac{x+2}{x-3} \div \frac{4}{x+2}\)[/tex]



Answer :

To find the rational expression equivalent to [tex]\(\frac{4}{a-3}\)[/tex], we need to consider each option given and verify whether it simplifies to the original expression.

First, let's review the operations involved for each option:

Option A: [tex]\(\frac{x+2}{x-3}-\frac{4}{x+2}\)[/tex]

Since option A involves subtraction, we need common denominators to combine these fractions. After finding the common denominator and combining the fractions, simplify the resulting expression.

Option B: [tex]\(\frac{z+2}{x-3}+\frac{4}{x+2}\)[/tex]

In option B, the numerators being added directly, first, we’d need common denominators. Combining or simplifying the resulting fraction might give us the form we seek.

Option C: [tex]\(\frac{x+2}{x-3} \cdot \frac{4}{x+2}\)[/tex]

Option C involves multiplication of fractions. When multiplying fractions, we multiply the numerators together and the denominators together:
[tex]\[ \frac{(x+2) \cdot 4}{(x-3) \cdot (x+2)} \][/tex]
Notice the [tex]\(x+2\)[/tex] in the numerator and denominator cancel out:
[tex]\[ \frac{4}{x-3} \][/tex]

Option D: [tex]\(\frac{x+2}{x-3} \div \frac{4}{x+2}\)[/tex]

Option D involves division of fractions, which is the same as multiplying by the reciprocal of the divisor:
[tex]\[ \frac{x+2}{x-3} \div \frac{4}{x+2} = \frac{x+2}{x-3} \cdot \frac{x+2}{4} \][/tex]
After rearranging:
[tex]\[ \frac{(x+2) \cdot (x+2)}{(x-3) \cdot 4} \][/tex]
This does not simplify to [tex]\(\frac{4}{a-3}\)[/tex].

From the explanation, it is clear that Option C is exactly the expression that simplifies to the original [tex]\(\frac{4}{a-3}\)[/tex].

So, the correct option is:

C. [tex]\(\frac{x+2}{x-3} \cdot \frac{4}{x+2}\)[/tex]