Question 113608: What values of b will make x^2 + bx + 2/5 a perfect square trinomial ? Found 2 solutions by checkley71, stanbon:Answer by checkley71(8403) (Show Source):
You can put this solution on YOUR website! X^2+BX+2/5
X^2+2(SQRT2/5)X+2/5 ANSWER.
OR X^2+2(SQRT0.4)+0.4 ANSWER.
OR X^2+1.2649X+0.4 ANSWER.
You can put this solution on YOUR website! What values of b will make x^2 + bx + 2/5 a perfect square trinomial ?
b = 2sqrt(2/5)
b = (2/5)sqrt10
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Why?
To get the 3rd term of a perfect square trinoial you
do the following:
1st: Divide by 2
2nd: Square the result
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So to go from the 3rd term to the 2nd you have to reverse the
procedure and use the inverse operations:
1st: Take the square root to undo the squaring
2nd: Multiply by 2 to undo the dividing
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Hope that helps.
Cheers,
Stan H.