This is a factored trinomial. In order to find the trinomial you need to use the distributive property.
x times 2x is 2x^2
x times -4 is -4x
5 times 2x is 10x
5 times -4 is -20
so you get 2x^2-4x+10x-20
combine the two x terms -4x+10x is 6x
2x^2+6x-20
There is a multiplying polynomials program that will do this for you if you have a calculator. The link will take you to the download page.
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