Question

Please help!....a root of x^2-5x-1=0 is

A. 1-√29/2
B. 5-√17/2
c. 1+ √29/2
D. 5+ √17/2
E. 5 +√29/2

Answer 1

uze das kuadratik phormula :)

Answer 2

\(\bf \textit{quadratic formula}\\
{\color{blue}{ 1}}x^2{\color{red}{ -5}}x{\color{green}{ -1}}=0
\qquad \qquad
x= \cfrac{ - {\color{red}{ b}} \pm \sqrt { {\color{red}{ b}}^2 -4{\color{blue}{ a}}{\color{green}{ c}}}}{2{\color{blue}{ a}}}\)

see what you get

Answer 3

\[x^2-5x-1=0\]\[(x^2-5x)=1\]\[x^2-5x\color{reD}{+\frac{25}{4}} = 1\color{red}{+\frac{25}{4}}\]\[\left(x-\frac{5}{2}\right)^2=\frac{29}{4}\]\[x=\pm \frac{\sqrt{29}}{2} +\frac{5}{2}\]

Answer 4

To find the portion in red is like completing the quadratic formula on the LHS, \(c=\left(\dfrac{-5}{2}\right)^2 = \dfrac{25}{4}\)

Answer 5

Thanks So much I just checked and its right!

Answer 6

Nice :)