I know the answer is 2,-10 can you please help me understand how to get that. thank you
Hi! Since the coefficient of the x^2 is 1 (1x^2), you have a quick method to do this.
First identify the factors of 20 in pairs (20*1, 10*2, 5*4)
Now which pair when added or subtracted from each other gives you 8?
20+1=21, 20-1=19, 10+2=12, 10-2=8, 5+4=9, 5-4=1
You need the 10 and 2.
One must be negative so that when multiplied, you get a -20 as a result. However, when added or subtracted, you need to get a positive 8. Therefore the 2 is negative (10+ (-2) = 8)
So your answer is (x-2)(x+10)
Hope this helps
Mike