how to factorise the difference of perfect squares. for the g on the top and j on the top
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Answer:
see explanation
Step-by-step explanation:
A difference of two squares is factored as
a² - b² = (a - b)(a + b)
(g)
1 - 81y²
= 1² - (9y)²
= (1 - 9y)(1 + 9y)
(j)
64x² - 25y²
= (8x)² - (5y)²
= (8x - 5y)(8x + 5y)