Questions: Express in simplest form: (x^2-49)/(7x-x^2).
Transcript text: Express in simplest form: $\frac{x^{2}-49}{7 x-x^{2}}$.
Solution
Solution Steps
To simplify the given expression \(\frac{x^{2}-49}{7x-x^{2}}\), we need to factor both the numerator and the denominator. The numerator \(x^2 - 49\) is a difference of squares, and the denominator \(7x - x^2\) can be factored by taking out the common factor.
Solution Approach
Factor the numerator \(x^2 - 49\) as \((x + 7)(x - 7)\).
Factor the denominator \(7x - x^2\) as \(-x(x - 7)\).
Simplify the fraction by canceling out the common factor \((x - 7)\).
Step 1: Factor the Numerator
The numerator \(x^2 - 49\) can be factored as a difference of squares:
\[
x^2 - 49 = (x + 7)(x - 7)
\]
Step 2: Factor the Denominator
The denominator \(7x - x^2\) can be rearranged and factored:
\[
7x - x^2 = -x^2 + 7x = -x(x - 7)
\]
Step 3: Simplify the Expression
Now, we can rewrite the original expression:
\[
\frac{x^2 - 49}{7x - x^2} = \frac{(x + 7)(x - 7)}{-x(x - 7)}
\]
We can cancel the common factor \((x - 7)\) from the numerator and denominator (assuming \(x \neq 7\)):
\[
= \frac{(x + 7)}{-x} = -\frac{(x + 7)}{x}
\]
Final Answer
The simplified form of the expression is:
\[
\boxed{-\frac{(x + 7)}{x}}
\]