anonymous 5 years ago x equals the square root of 8 x

1. watchmath

$$x=\sqrt{8x}$$\ Square both sides $$x^2=8x$$ $$x^2-8x=0$$ $$x(x-8)=0$$ $$x=0,8$$

2. anonymous

X^x = 8x X = 8

3. anonymous

Sorry that's x^2 = 8x X = 8

4. anonymous

um watch math can you do it if it has an equation on both sides or is it different

5. anonymous

See if x^2 = 8x then X*x = 8*x Divide both sides by x X=8

6. watchmath

In this problem we need to bring everything to one side of the equation so that we can factor it. Otherwise if you divide by $$x$$ like ishwan did you will loose one solution, namely $$x=0$$.

7. anonymous

an example is n-4= the spuare root of 12-3n

8. watchmath

The idea is still the same. You square both sides and collect everything on one side. $$(n-4)^2=12-3n$$ $$n^2-8n+16=12-3n$$ $$n^2-5n+4=0$$ $$(n-4)(n-1)=0$$ $$n=4$$ or $$n=1$$ Double check to the original equation shows that $$n=1$$ is not a solution. Thus $$n=4$$ is the only solution. (press good answer button if my answer is helpful :D )

9. anonymous

Watch math is correct

10. anonymous

alright thanks i need help with one more the square root of b-1-b=negative seven

11. watchmath

Post as a new question :)

12. anonymous

the square root of b-1-b equals negative seven

13. anonymous

shawna can paint a fence in 5 hrs. Jassie can paint the same fence in 10 hrs. how long will it take them to paint the fence together