Solved examples: Identifying constants, variables, and terms in expressions

📚 Quick Study Guide

• 🔢 Constant: A fixed value that doesn't change. It's just a number! For example, in the expression $3x + 5$, the constant is $5$.
• 🔀 Variable: A symbol (usually a letter) that represents an unknown value. It can change. In the expression $3x + 5$, the variable is $x$.
• ➕ Term: A single number or variable, or numbers and variables multiplied together. Terms are separated by + or - signs. In the expression $3x + 5$, the terms are $3x$ and $5$.
• 💡 Coefficient: The number multiplied by a variable. In the term $3x$, the coefficient is $3$.
• 📝 Expression: A combination of constants, variables, and terms. For example, $4y - 7 + 2z$ is an expression.

🧪 Practice Quiz

1. Which of the following is a constant in the expression $7y + 9 - 2x$?

   1. A) $7$
   2. B) $y$
   3. C) $9$
   4. D) $2x$

2. Identify the variable in the expression $15 - 4z + z^2$

   1. A) $15$
   2. B) $4$
   3. C) $z$
   4. D) $z^2$

3. How many terms are in the expression $6a - 2b + 8c - 1$?

   1. A) 2
   2. B) 3
   3. C) 4
   4. D) 5

4. What is the coefficient of $x$ in the term $-5x$?

   1. A) $5$
   2. B) $x$
   3. C) $-5$
   4. D) $-5x$

5. Which of the following is an expression?

   1. A) $y = 3$
   2. B) $2 + 5 = 7$
   3. C) $4x - 2$
   4. D) $8$

6. In the expression $p^2 + 4p - 10$, what is the constant term?

   1. A) $p^2$
   2. B) $4p$
   3. C) $4$
   4. D) $-10$

7. Identify all the variables in the following expression: $3x + 4y - z + 6$

   1. A) $3, 4, 1$
   2. B) $x, y, z$
   3. C) $6$
   4. D) $3x, 4y, z$