## anonymous 5 years ago (squaredrootof)x-5=(squaredrootof)x-1 [the -1 is not inside the squaredroot) :)

1. dumbcow

square both sides you have to FOIL the right side

2. anonymous

uhhh.... i need help with that :///

3. anonymous

$\sqrt{x-5}=\sqrt{x}-1$$(\sqrt{x-5})^2=(\sqrt{x}-1)^2$v-------------^$(\sqrt{x}-1)(\sqrt{x}-1)$FOIL $(x-\sqrt{x}-\sqrt{x}+1)$$(x-2\sqrt{x}-1)$$x-5=x-2\sqrt{x}+1$-x -1 -x -1 $-6=-2\sqrt{x}$/-2 /-2$3=\sqrt{x}$$(3)^2=(\sqrt{x})^2$$9=x$Finished!!!

4. anonymous

woah.. id nt get the foil.. why woudl (sqrdrt) of x multiplied by the same thing give x?

5. anonymous

I forget the name of the actual rule. But simply it's$(x^2)(x^3)=x^5$What you do is take the exponents and add them together.$\sqrt{x}=x ^{1/2}$Therefore$(\sqrt{x})(\sqrt{x})=(x ^{1/2})(x ^{1/2})$Which then makes$(x ^{1/2})(x ^{1/2})=x^1$or x.

6. anonymous

oh. haha. sorry :) and i don't get the x-1-x-1 part.. :(

7. anonymous

$(x ^{a})(x ^{b})=x ^{a+b}$ That's the rule.

8. anonymous

I'm subtracting x and 1 from each side.

9. anonymous

ooohh... i see it now:) can you repeart that last part? after the little isue i just did? my computer won't show anything after that. :(

10. anonymous

after the -x-1-x-1?

11. anonymous

yes.

12. anonymous

$x-5=x-2\sqrt{x}+1$-x -1 -x -1$-6=-2\sqrt{x}$/-2 /-2$3=\sqrt{x}$$(3)^2=(\sqrt{x})^2$$9=x$

13. anonymous

what do the /-2/-2 stand for?

14. anonymous

Divide by -2 on both sides.

15. anonymous

okay. :)

16. anonymous

I was taught "The Granny Rule: Granny's are fair, what they do to one chile they do to the other." Same with algebra, what you do to one side of the equation you have to do to the other.

17. anonymous

*child*

18. anonymous

mahaha:) that's a good way to remember it:D

Find more explanations on OpenStudy