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# Solving equations watch

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1. Find the value k for which 5x^2-2x+k=0 has exactly one solution.

What should i do to work this out
2. If it has one solution, that means the roots are equal hence b^2-4ac=0. Plug that in and solve.
3. Are u familiar with the roots of a quadratic.

If b^2-4ac>0 then the quadratic has two real roots.

If b^2-4ac=0 then the quadratic has 1 real root.

If b^2-4ac<0 then the quadratic has no real roots.
4. (Original post by thekidwhogames)
If it has one solution, that means the roots are equal hence b^2-4ac=0. Plug that in and solve.
Thanks that has worked.
5. (Original post by Shaanv)
Are u familiar with the roots of a quadratic.

If b^2-4ac>0 then the quadratic has two real roots.

If b^2-4ac=0 then the quadratic has 1 real root.

If b^2-4ac<0 then the quadratic has no real roots.
Thanks, am i right in saying k=1/5
6. (Original post by FinnManley)
Thanks, am i right in saying k=1/5
Yes.
7. (Original post by FinnManley)
Thanks, am i right in saying k=1/5
Yes thats correct. An alternative solution is to note that if a quadratic has just one solution then that means it can be written in the form a(x+b)^2 e.g it has no constant term when completing the square and this will easily give you the value of k.

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