Answer:
Step-by-step explanation:
3)
a) (- 5 + x)(x + 4)
We would apply the distributive property by expanding the brackets, it becomes
- 5x + 4 × - 5 + x² + 4 × x
- 5x - 20 + x² + 4x
x² - 5x + 4x - 20
x² - x - 20
b) the product of 5 + x and x - 4 is
(5 + x)(x - 4) = 5x - 20 + x² - 4x
= x² + 5x - 4x - 20
= x² + x - 20
Therefore,
(- 5 + x)(x + 4) and (5 + x)(x - 4) are not equal.
c) (2x + 5)(3x² + 4x - 3)
Expanding the brackets, it becomes
6x³ + 8x² - 6x + 15x² + 20x - 15
Collecting like terms, it becomes
6x³ + 8x² + 15x² + 20x - 6x - 15
= 6x³ + 23x² + 14x - 15
