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_Mayday_
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[SOLVED] Discriminant Related Question
Question
[tex]x^2 - 8x - 29 = (x+a)^2 +b[/tex], where a and b are constant.
NOTE: The equals sign should be an always equals sign, so like three lines under each other
(a) Find the value of a and b
(b)Hence, or otherwise show the roots of [tex]x^2 - 8x - 29 = 0[/tex] are [tex]c =+/- d\sqrt5[/tex] where c and d are integers.
Attempt
(a)[tex]x^2 - 8x - 29 = (x+a)^2 +b[/tex]
[tex](x-4)^2 - 16 - 29 = (x+a)^2 +b[/tex]
a = -4
b = -45
(b) Erm...not sure, as it says roots I will assume it means two roots so [tex]b^2 - 4ac > 0[/tex]
64 + 116 > 0, yes this is all alright but I am not sure how to get it in the form [tex]c =+/- d\sqrt5[/tex]
_Mayday_
Question
[tex]x^2 - 8x - 29 = (x+a)^2 +b[/tex], where a and b are constant.
NOTE: The equals sign should be an always equals sign, so like three lines under each other
(a) Find the value of a and b
(b)Hence, or otherwise show the roots of [tex]x^2 - 8x - 29 = 0[/tex] are [tex]c =+/- d\sqrt5[/tex] where c and d are integers.
Attempt
(a)[tex]x^2 - 8x - 29 = (x+a)^2 +b[/tex]
[tex](x-4)^2 - 16 - 29 = (x+a)^2 +b[/tex]
a = -4
b = -45
(b) Erm...not sure, as it says roots I will assume it means two roots so [tex]b^2 - 4ac > 0[/tex]
64 + 116 > 0, yes this is all alright but I am not sure how to get it in the form [tex]c =+/- d\sqrt5[/tex]
_Mayday_