Factorise the following.
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Answer:
iii. (p - 7)(p - 3)
iv.(x - 8)(x + 4)
Step-by-step explanation:
iii. p² - 10p + 21
= p² - (7 + 3)p + 21
= p² -7p -3p + 21
= p(p - 7) - 3(p - 7)
= (p - 7)(p - 3)
iv. x² - 4x - 32
= x² - (8 - 4)x - 32
= x² - 8x + 4x - 32
= x(x - 8) + 4(x - 8)
= (x - 8)(x + 4)