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# Trinomial help watch

1. So i need to factorise 2x^2+13x+15

The way Ive been taught is 2 x 15 is 30, then use factors of 30.
All the calculators for this say the factors you use are 3 and 10 but they dont add up into 15

Where am I going wrong?
2. (Original post by Peterson957)
So i need to factorise 2x^2+13x+15

The way Ive been taught is 2 x 15 is 30, then use factors of 30.
All the calculators for this say the factors you use are 3 and 10 but they dont add up into 15

Where am I going wrong?

The two numbers you're looking for should multiply to give and add to give .

So in this case, the two numbers should add multiply to give 30 and add to give 13.
3. (Original post by Notnek)

The two numbers you're looking for should multiply to give and add to give .

So in this case, the two numbers should add multiply to give 15 and add to give 13.
I think you mean

So in this case, the two numbers should add multiply to give 30 and add to give 13.
4. (Original post by DFranklin)
I think you mean
Thanks, that was an unfortunate mistake.

Peterson957 Sorry if that confused you. I've edited my post now.

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