Worked example Simplify the following. (i) 4x + 6y + x + 4y (iii) 2 xy2
− x2 y + 10xy2
Solution (i)
(iii) − 23x2 y x
x x x
(ii) 2 a2 (iv) 4 a2
− b + 4 a2 b3
− 6 a3
b2
+ 3 a2
b3
− 9 a3
b2
− 4 a2
b3
y x y
y
(ii)
a2 a2 a2
(iv)
b a b
a2 b
Practice questions 8.1
1. Copy and complete the following table, identifying the terms as being either like terms or unlike terms. Give a reason for your answer in each case. Terms
Like terms/Unlike terms
x, 2x, 4x 3, a, –3a 3 x2 5 x 3 9a 2
, 2 x 2 y 2 b 3
, − 4x
, − 3 x 3 , − 8a 3
y 2 b 2
2. Identify the coeffi cient, the variable, and the constant term of the following expressions.
(i) 4x + 6 (ii) 10 – 4y (iii) 12 + x
(iv) 0·5α − 5 (v) 3
(vi) a + 0·78
3. Identify all of the ‘invisible’ Maths in each of the following.
(i) x (ii) 2x (iii) 5x − y
4. Simplify the following. (i) a + a + a + a + a + a (ii) x + y + x + y + x (iii) 4x + 2y + 6x + 10y