## LaurenAshley1201 Group Title help :) multiply expression 2 years ago 2 years ago

1. LaurenAshley1201 Group Title

$2\sqrt{6}\times \sqrt{10}$

2. Calcmathlete Group Title

Multiply them seperately... $2\sqrt6 \times \sqrt{10} \implies 2\sqrt{6 \times 10} \implies 2 \sqrt{2 \times 3 \times 2 \times 5} \implies~?$

3. Calcmathlete Group Title

Can you finish from there? Can you simplify the radical?

4. violy Group Title

|dw:1344751807375:dw| here is an example. :)

5. waterineyes Group Title

@merp it is better if you do it here by your own..

6. waterineyes Group Title

@LaurenAshley1201 $\implies 2 \sqrt{\color{blue}{\underline{2 \times 2}} \times 3 \times 5} = ??$

7. LaurenAshley1201 Group Title

2 sqrt 60? i dont think im doing it right

8. waterineyes Group Title

You can solve further for $$\sqrt{60}$$..

9. LaurenAshley1201 Group Title

2 sqrt 15

10. waterineyes Group Title

$\sqrt{60} = \sqrt{\color{blue}{\underline{2 \times 2}} \times 3 \times 5}$ Can you go further..??

11. violy Group Title

think of a perfect square number that can go into 60.

12. waterineyes Group Title

Yes..

13. waterineyes Group Title

There is one 2 outside too..

14. Calcmathlete Group Title

We have broken 60 down into prime factors for you. Remember this? $\sqrt{x \times x} = x$Use the same rule...

15. waterineyes Group Title

$2 \times 2 \sqrt{15} = ??$

16. violy Group Title

do you mean sqrt (4 * 15) ?

17. waterineyes Group Title

No..

18. LaurenAshley1201 Group Title

i dont know how to go any furhter

19. waterineyes Group Title

$$\sqrt{60}$$ is how much ??

20. waterineyes Group Title

you have solved it above..

21. waterineyes Group Title

$\sqrt{60} = \sqrt{\color{blue}{\underline{2 \times 2}} \times 3 \times 5} = ??$

22. violy Group Title

its like sqrt( 5 x 5) = sqrt (25) = 5.

23. waterineyes Group Title

Where are you having problem @LaurenAshley1201

24. violy Group Title

let me give you an example: $\sqrt{45}=\sqrt{3*3*5}=\sqrt{9} * \sqrt{5} = 3\sqrt{5}$

25. LaurenAshley1201 Group Title

sqrt of 60 is 2 sqrt 15

26. violy Group Title

you got it right now! :)

27. waterineyes Group Title

In square root you can pull out one from a pair like this: $\sqrt{4 \times 4 \times 5}$ Here you can see there are two 4's. SO you can take one 4 outside and there will remain no 4 in the square root brackets: So it becomes; $\sqrt{\color{green}{\underline{ 4 \times 4} \times 5}} \implies 4 \sqrt{5}$

28. Calcmathlete Group Title

Ok. Do you understand this at the very least? $\sqrt{3 \times 3} = \sqrt{3^2} = \sqrt{9} = 3\color{red}{\huge??????}$

29. LaurenAshley1201 Group Title

yes i do

30. Calcmathlete Group Title

THat's basically what you're doing here, it's just that you can make sense of it without showing all of the steps because you know the end result which is why we know that$\sqrt{60} = \sqrt{2 \times 2 \times 3 \times 5} = 2\sqrt{15}$

31. waterineyes Group Title

$2 \sqrt{60} = 2 \times (2 \sqrt{15}) = ??$

32. LaurenAshley1201 Group Title

@Calcmathlete would that be my final answer?

33. Calcmathlete Group Title

Not quite...you forgot the 2 that was already out there... $2 \times 2\sqrt{15} = ?$

34. violy Group Title

not yet, example: $3*(4\sqrt{5}) = 3*4\sqrt{5} = 12\sqrt{5}$

35. LaurenAshley1201 Group Title

i figuired it out,with everyones help ! thanks everyone

36. Calcmathlete Group Title