Question

Разложите на множители
$5x {}^{2} - 5y {}^{2}$
$(5a + 6) {}^{2} - 81$
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Answer 1

Ответ:

5x²-5y²=5(x²-y²)=5(x-y)(x+y).

(5a+6)²-81=(5a+6-9)(5a+6+9)=(5a-3)(5a+15)=5(5a-3)(a+3).

Answer 2

Ответ:

$5x^2-5y^2=5(x-y)(x+y)\\\\\\(5a+6)^2-81=(5a+6-9)(5a+6+9)=(5a-3)(5a+15)=\\\\=5(5a-3)(a+3)$