Evaluate the rational expression below at x = − 1 x=-1 12 x + 3 \frac{12}{x+3}

problem here asks us to evaluate the rational expression below at x equals negative one. So all that means is I need to take every place that I see x and replace it with negative one. So we're going to end up getting 12 over negative one plus three. Now, negative one plus three, that's just gonna give us two, and twelve divided by two is six, so six would be the answer to this problem.

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8. Rational Expressions and Equations

Simplifying Rational Expressions

Beginning & Intermediate Algebra

8. Rational Expressions and Equations

Simplifying Rational Expressions

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Multiple Choice

Evaluate the rational expression below at $x = - 1$
$\frac{12}{x + 3}$

$4$

$3$

$12$

$6$

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Verified step by step guidance

Identify the given rational expression: $\frac{12}{x+3}$.

Substitute the given value $x = -1$ into the expression, replacing every $x$ with $-1$.

Rewrite the expression after substitution as $\frac{12}{-1 + 3}$.

Simplify the denominator by performing the addition inside the denominator: calculate $-1 + 3$.

Express the simplified rational expression as $\frac{12}{\text{(result from previous step)}}$ and note that this is the value of the expression at $x = -1$.