Letters and the parts of expressions
Answers are for parents and teachers.
1
A bus has b children on it and 4 more get on. Write an expression for the children now.
b + 4.
2
A school buys n notebooks at 9 LE each. Write the cost, then find it for n = 6.
9n LE. For n = 6 it is 9 × 6 = 54 LE.
3
In 5x + 3y + 2x + 8 list the terms, the coefficients, the constant and the like terms.
Terms: 5x, 3y, 2x, 8. Coefficients: 5, 3, 2. Constant: 8. Like terms: 5x and 2x.
4
Say n − 4 and n ÷ 4 in words.
n − 4 is “4 less than n”. n ÷ 4 is “n divided by 4”.
5
Explain why 4x with x = 7 is 28 and not 47.
4x means 4 times x, so 4 × 7 = 28. Writing 4 and 7 side by side would be the number forty-seven, which is not a product.