8.1 Algebraic notation and vocabulary — Practise

1. Write $7x$ as repeated addition, then state its coefficient.

Answer: Seven groups of $x$; coefficient $7$.

2. Write an expression for five more than $n$.

Answer: $n+5$.

3. Evaluate $3x+2$ when $x=3$.

Answer: $3(3)+2=11$.

4. State the terms and coefficients in $4a+4b$.

Answer: Terms $4a$ and $4b$; each coefficient is $4$.

5. If each item costs £5, write and evaluate the total cost $C=5n$ for $n

Answer: $C=5(6)=£30$.

6. Evaluate $2m+1$ when $m=4$.

Answer: The expression $2m+1$ becomes $2(4)+1=9$.

7. Write an expression for three fewer than $t$.

Answer: $t-3$.

8. Is $2m+1=9$ an expression or equation?

Answer: It is an equation because it states equality.