Question

factorise: 25 - p² - q² –2pq​

Answer 1

Step-by-step explanation:

$25 - {p}^{2} - {q}^{2} - 2pq \\ = {5}^{2} - ( {p}^{2} + 2pq + {q}^{2} ) \\ = {5}^{2} - (p + q) ^{2} \\ = (5 + p + q)(5 - p - q)$

That is in term of

${a}^{2} - {b}^{2} \\ = (a + b)(a - b)$

Answer 2

Answer:

(5+p+q)(5-p-q)

Step-by-step explanation:

25- p^2- q^2 - 2pq

= 5^2 - (p^2 + 2pq + q^2)

= 5^2 - (p+q)^2 ( cause (a+b)^2 = a^2 + 2ab + b^2 )

= (5 + p + q ) (5 - p - q ) (as a^2-b^2 =(a+b)(a-b) )