SOLUTION: I need to find value of d in the following problem. Perfect square y^2-10y+d

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Question 190630: I need to find value of d in the following problem. Perfect square
y^2-10y+d
Found 2 solutions by jim_thompson5910, Earlsdon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
If the expression x%5E2%2Bbx%2Bc is a perfect square, then c=%28b%2F2%29%5E2 (ie take half of b and square it to get c)


So in this case, b=-10. So d=%28-10%2F2%29%5E2=%28-5%29%5E2=25 which means that d=25. So the perfect square is y%5E2-10y%2B25

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Find d if y%5E2-10y%2Bd is a perfect square:
In order for y%5E2-10y%2Bd to be a perfect square, d must be the square of half the y-coefficient, or %2810%2F2%29%5E2+=+highlight%2825%29, so....
y%5E2-10y%2B25+=+%28y-5%29%5E2