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(f) Sum of numbers a and b subtracted from their product
(g) Three times r added to one-fifth the product of p and q

Solution: (a) z + x (b) x 2 (c) 1 pq (d) xy – x 3
2 4
1
(e) 3mn + 4 (f) ab – (a + b) (g) 3r + pq
5
Example 2: A. Identify the terms and their factors in the following expressions. Show the terms
and factors by tree diagrams.
2
2
(a) x + 5 (b) 1 + 3x + x (c) 3x y – 4xy 2
B. Identify the terms and their factors in the expressions given below:
2
(a) 3x + 2 (b) 3xy + 4x 2 (c) pq – qr (d) 0.2a + 0.3b 2
2
Solution: A. (a) x + 5 Expression (b) 1 + 3x + x Expression

x 5 Terms 1 3x x 2 Terms

3 x x x Factors
(c) 3x y – 4xy 2 Expression
2

2
2
3x y –4xy Terms
3 x x y –4 x y y Factors

B. Expression Terms Factors
(a) 3x + 2 3x, 2 3, x ; 2, 1
(b) 3xy + 4x 2 3xy, 4x 2 3, x, y ; 4, x, x

(c) pq – qr pq, – qr p, q ; –q, r
2
2
(d) 0.2a + 0.3b 2 0.2a , 0.3b 2 0.2, a, a ; 0.3, b, b
Example 3: Identify the numerical coefficients of the terms (other than constants) in the following
expressions:
2
2
(a) 6 – 3t (b) 1 + x + x + x 3
2
(c) x + 3xy + 7y (d) 50 m – 1 n
100
Solution: Expression Algebraic Terms Numerical Coefficient

(a) 6 – 3t 2 –3t 2 –3

x 1
2
(b) 1 + x + x + x 3 x 2 1
x 3 1
x 1
(c) x + 3xy + 7y 2 3xy 3
7y 2 7
50 m 50

(d) 50 m – 1 n – 1 n – 1
100 100 100

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