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Factorisation

Hey can anyone explain how to factorise 7p^2 - 6pq- 16q^2?
Original post by XchickenX
Hey can anyone explain how to factorise 7p^2 - 6pq- 16q^2?


Have a good eye:

(7p214pq)+(8pq16q2)(7p^2 -14pq) + (8pq - 16q^2)

Otherwise, you can rewrite as q2(7p2q26pq16)q^2(7\frac{p^2}{q^2}-6\frac{p}{q}-16) and factorise the inside polynomial in terms of pq\frac{p}{q} before multiplying through by q2q^2 (note: distribute one qq into each bracket)
Original post by RDKGames
Have a good eye:

(7p214pq)+(8pq16q2)(7p^2 -14pq) + (8pq - 16q^2)

Otherwise, you can rewrite as q2(7p2q26pq16)q^2(7\frac{p^2}{q^2}-6\frac{p}{q}-16) and factorise the inside polynomial in terms of pq\frac{p}{q} before multiplying through by q2q^2 (note: distribute one qq into each bracket)


You don't need to take out q^2. Simply observe that it's the same as factorising 7x^2-6x-16, only with p and q instead of x and constant.
Original post by Prasiortle
You don't need to take out q^2. Simply observe that it's the same as factorising 7x^2-6x-16, only with p and q instead of x and constant.


The reason I didn't mention this is because it looks like too much of a jump for someone who doesn't seem to have a slightest idea on where to start.

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