+279 Factor the trinomial below. Write each factor as a polynomial in descending order.
8x^2 - 10x - 25
+118687 8x^2 - 10x - 25
8*-25=-200
So I want 2 numbers that add to -10 and multiply to -200
The bigger one will be negative and the smaller one will be positive (absolute values I mean)
The fairly obvious combination is -20 and 10
-10x is replaced with -20x+10x
= 8x^2 -20x+10x - 25
Now factorise in pairs
= 4x(2x-5) + 5(2x-5)
= (4x+5)(2x-5)
+279 Thank you Melody, I think i understand it better now
(you might have just taught me something i would have never thought about using or doing)
+118687 That is good. 
It is a good way to do these but a lot of teachers teach what I think is a more complicated method.
+2864 My teacher taught in the same way as you did, Melody. But I personally use the Table Method
