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# Helppp how to solve x=5√(x) - 6 watch

1. (Original post by KittyRe-play)
So first I square the equation to get rid of the square root? That will give me x squared minus 25x plus 36?
You can square both sides of the equation if you wish - that is an alternative method

but you have not done so correctly

Have you covered this topic in school?
2. (Original post by KittyRe-play)
How?

Let so that

clearly this transforms our initial equation into which can then be solved for y, and then using the fact we can find solutions for x.
3. (Original post by TenOfThem)
You can square both sides of the equation if you wish - that is an alternative method

but you have not done so correctly

Have you covered this topic in school?
Sorry i meant x squared minus 5x plus 36?? Do you not square the 5 as well?
4. (Original post by KittyRe-play)
Sorry i meant x squared minus 5x plus 36?? Do you not square the 5 as well?
You can't apply an operation to each element in an equation separately.
.
Eg.
.

Two ways to solve have been mentioned.
2)Squaring both sides.
5. (Original post by alpen)

Let so that

clearly this transforms our initial equation into which can then be solved for y, and then using the fact we can find solutions for x.
Yeah so that would be y=3 & y=2 right?
6. (Original post by keromedic)
You can't apply an operation to each element in an equation separately.
.
Eg.
.
you just said 6=6^2
7. (Original post by KittyRe-play)
Sorry i meant x squared minus 5x plus 36?? Do you not square the 5 as well?

and square both sides

it is imo better to just solve the quadratic equation without squaring but you do not seem happy with the method shown in the thread - so try this
8. (Original post by KittyRe-play)
Yeah so that would be y=3 & y=2 right?
yes

so what is x
9. (Original post by KittyRe-play)
Yeah so that would be y=3 & y=2 right?
indeed, so or
10. (Original post by alpen)
you just said 6=6^2
I edited it -_-.
11. (Original post by alpen)
indeed, so or
Thank you.
12. (Original post by TenOfThem)

and square both sides

it is imo better to just solve the quadratic equation without squaring but you do not seem happy with the method shown in the thread - so try this
Yes indeed as I want to know this method. So if I square that do I get x^2+36=25x? What I don't get is when squaring do you square the coefficient of the square root of x, which in this case is 5?
13. (Original post by KittyRe-play)
Yes indeed as I want to know this method. So if I square that do I get x^2+36=25x? What I don't get is when squaring do you square the coefficient of the square root of x, which in this case is 5?
the 25x is fine but the does not equal
14. I get it guys thanks a lot I guess that y method is better than what I was going for! Cheers.
15. (Original post by TenOfThem)
the 25x is fine but the does not equal
Its x^2+12x+36=25x?
16. (Original post by KittyRe-play)
I get it guys thanks a lot I guess that y method is better than what I was going for! Cheers.
ok

it is the preferred method anyway
17. (Original post by KittyRe-play)
Its x^2+12x+36=25x?
yes, it is
18. (Original post by TenOfThem)
yes, it is
So then I minus 25x which gives x^2-13x+36=0
Solving this quadratic then gives x=4 and x=9
Hallaluya I get it!
19. (Original post by KittyRe-play)
So then I minus 25x which gives x^2-13x+36=0
Solving this quadratic then gives x=4 and x=9
Hallaluya I get it!
20. (Original post by TenOfThem)
But then using the y method the solutions are x=3 & x=2 and it's not the same as 4 and 9. So is that incorrect?

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