SOLUTION: will you please help me factor this equation: 16k squared minus 80k plus 100. thankyou

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Question 7201: will you please help me factor this equation: 16k squared minus 80k plus 100. thankyou
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Factor:
16k%5E2+-+80k+%2B+100 Factor a 4 first.
4%284k%5E2+-+20k+%2B+25%29 Now try:
4%282k+-+5%29%282k+-+5%29%29
The reason to try a -5 constant term in the factors is because you want to get a +25 as the constant in the second equation The only way is to have (-5)(-5) in the factors. Well, (-1)(-25) also = +25 but you can quickly see that this would not work.
So the complete factorisation is: 4(2k-5)(2k-5)
Check the solution by using FOIL:
4%282k-5%29%282k-5%29+=+4%284k%5E2+-+10k+-+10k+%2B+25%29 = 16k%5E2+-+80k+%2B+100