Review of Variables
While arithmetic deals primarily with operations with numbers, in algebra, you will deal with expressions that involve variables–letters that represent real numbers. Watch this lecture series to review the concept of a variable and the conventional way to write basic expressions involving variables. Complete the interactive exercises.
Evaluating expressions with one variable - Questions
Answers
1. Let's substitute \(12\) for \(n\).
\(\frac{n}{6} + 2 \)
= \(\frac{12}{6} + 2 \)
= \( 2 + 2 \)
= \(4\)
2. Let's substitute \(3\) for \(x\).
\(6 + x\)
= \( 6 + 3\)
= \(9\)
3. Let's substitute \(3\) for \(k\).
\(\frac{15}{k} \)
= \(\frac{15}{3}\)
= \(5\)
4. Let's substitute \(5\) for \(g\).
\(4g - 12 \)
= \(4(5) - 12 \)
= \( 20 - 12\)
= \(8\)
5. Let's substitute \(12\) for \(j\).
\(\frac{j}{4} \)
= \(\frac{12}{4} \)
= \(3\)
6. Let's substitute \(7\) for \(c\).
\( c - 2\)
= \( 7 - 2\)
= \(5\)
7. Let's substitute \(4\) for \(S\).
\( 9 - \frac{8}{S}\)
= \( 9 - \frac{8}{4}\)
= \( 9 - 2\)
= \(7\)