Ask your own question, for FREE!
Mathematics 14 Online
OpenStudy (anonymous):

x^2-5x+1+0

OpenStudy (anonymous):

x^2-5x+1=0

OpenStudy (anonymous):

Are you meant to find x or just factorise? If you are to find x then follow this. \[x^2-5x+1=0\] Use the quadratic formula. \[x=\frac{ -b \pm \sqrt{b^2-4ac} }{ 2a }\]

OpenStudy (anonymous):

it says to find all real solutions of the equation by completing the square

OpenStudy (anonymous):

ah okay, then don't follow what I did there.

OpenStudy (anonymous):

\[x^2-5x=-1\] \[(x-(\frac{ 5 }{ 2 }))=-1+(\frac{ 5 }{ 2 })^{2}\]

OpenStudy (anonymous):

To complete the square, move the constant to the other side. \[x^2-ax\] \[(x-\frac{a}{2})^{2}\]

OpenStudy (anonymous):

I did a mistake in the second line.

OpenStudy (anonymous):

meant to be \[(x-\frac{ 5 }{ 2 })^2=-1+(\frac{ 5 }{ 2 })^2\]

OpenStudy (anonymous):

I had it x^2-5x- 25/4= -1 then moved the 25/4 to the other side

OpenStudy (anonymous):

That's not how you complete the square.

OpenStudy (anonymous):

so I was at x^2-5x= -1 + 6 1/4 which equaled 5 1/4

OpenStudy (anonymous):

You're not meant to expand the LHS.

OpenStudy (anonymous):

oh ok

OpenStudy (anonymous):

\[(x-\frac{ 5 }{ 2 })^2=\frac{ 21 }{ 4 }\] \[x-\frac{ 5 }{ 2 }=\frac{ \pm \sqrt{21} }{ 2 }\]

OpenStudy (anonymous):

Move the -5/2 to the RHS.

OpenStudy (anonymous):

So then it would be \[x=\frac{ \pm \sqrt{21} }{ 2 }+\frac{ 5 }{ 2 }\] \[x=\frac{ 5\pm \sqrt{21} }{ 2 }\]

OpenStudy (anonymous):

thanks for the help

OpenStudy (anonymous):

No worries.

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!