Expand your horizons with the diverse and informative answers found on IDNLearn.com. Find the answers you need quickly and accurately with help from our knowledgeable and experienced experts.

Simplify the following mathematical expressions:

\begin{tabular}{|c|c|}
\hline
Model & Expression \\
\hline
1 & [tex]$4 + 5$[/tex] \\
\hline
2 & [tex]$4(5)$[/tex] \\
\hline
3 & 20 \\
\hline
4 & [tex]$5(4)$[/tex] \\
\hline
5 & [tex]$b(5)$[/tex] \\
\hline
\end{tabular}

Which expressions represent this model? Check all that apply.


Sagot :

Let's go through each expression step by step to determine its correctness and whether it matches the given model. Based on the numerical results provided, here's the detailed solution:

1. Expression [tex]\(4 + 5\)[/tex]:
- When we evaluate [tex]\(4 + 5\)[/tex], we get [tex]\(9\)[/tex].
- Therefore, the numerical result for [tex]\(4 + 5\)[/tex] is [tex]\(9\)[/tex].
- This does not match with 20, so it does not represent the model.

2. Expression [tex]\(4(5)\)[/tex]:
- This expression is equivalent to [tex]\(4 \times 5\)[/tex].
- Evaluating [tex]\(4 \times 5\)[/tex] gives us [tex]\(20\)[/tex].
- Therefore, the numerical result for [tex]\(4(5)\)[/tex] is [tex]\(20\)[/tex].
- This matches with the model, so it does represent the model.

3. Expression [tex]\(20\)[/tex]:
- This value is given without the need for further calculation.
- The value is [tex]\(20\)[/tex].
- This directly matches the model, so it does represent the model.

4. Expression [tex]\(5(4)\)[/tex]:
- This expression is equivalent to [tex]\(5 \times 4\)[/tex].
- Evaluating [tex]\(5 \times 4\)[/tex] also gives us [tex]\(20\)[/tex].
- Therefore, the numerical result for [tex]\(5(4)\)[/tex] is [tex]\(20\)[/tex].
- This matches with the model, so it does represent the model.

5. Expression [tex]\(b(5)\)[/tex]:
- The variable [tex]\(b\)[/tex] is undefined in this context.
- Without knowing the value of [tex]\(b\)[/tex], we cannot evaluate this expression.
- For this reason, it is invalid and does not represent the model.

6. Expression [tex]\(lnfes\)[/tex]:
- This sequence of characters does not represent a recognizable mathematical expression or value.
- It appears nonsensical and cannot be evaluated.
- Therefore, it is invalid and does not represent the model.

Given the evaluations above, we check which expressions represent the given model:

- [tex]\(4 + 5\)[/tex]: Does not represent the model.
- [tex]\(4(5)\)[/tex]: Represents the model.
- [tex]\(20\)[/tex]: Represents the model.
- [tex]\(5(4)\)[/tex]: Represents the model.
- [tex]\(b(5)\)[/tex]: Does not represent the model.
- [tex]\(lnfes\)[/tex]: Does not represent the model.

Therefore, the expressions that represent the model are:

[tex]\[ 4(5), 20, \text{and} 5(4) \][/tex]