Home › SPM Maths › Quadratic Expressions and Equations › 2.1 Quadratic Expression (Sample Questions)

2.1 Quadratic Expression (Sample Questions)

Posted on by

Example 1:
Form a quadratic expression by multiplying each of the following.
(a) (6p – 2)(2p – 1)
(b)   (m + 5)(4 – 7m)
(c)    (x + 2) (2x – 3)

Solution:
(a) (6p – 2)(2p – 1)
= (6p)(2p) + (6p)(-1) + (-2)(2p) +(-2)(-1)
= 12p2 – 6p – 4p + 2
= 12p2 – 10p + 2

(b) (m + 5)(4 – 7m)
= (m)(4) + (m)(-7m) + (5)(4) + (5)(-7m)
= 4m – 7m2 + 20 – 35m
= – 7m2 – 31m+ 20

(c) (x + 2) (2x – 3)
= (x)(2x) + (x)(-3) + (2)(2x) + (2)(-3)
= 2x2-3x + 4x – 6
= 2x2 + x - 6