Question

Nakim simplified 3 times the square root of 2x plus x times the square root of 8x minus 5 times the square root of 18x and got -10x times the square root of 2x for an answer.

Part 1: Using complete sentences, explain what Nakim did wrong.

Part 2: Show all your work to simplify the expression.

(You can use "sqrt()" to show a square root. For example, 7 times the square root of a can be written as 7sqrt(a). )

Answer 1

@terenzreignz

Answer 2

http://openstudy.com/users/nory#/updates/51f0b730e4b00daf471b0caa

Answer 3

^

Answer 4

Exemplary patience :)

Answer 5

3\(\sqrt{2x}\) + x \(\sqrt{8x}\) - 5 \(\sqrt{18x}\) = -10x\(\sqrt{2x}\)

Answer 6

that is equal to

3 \(\sqrt{2x}\) + 2x \(\sqrt{2x}\) -15 \(\sqrt{2x}\)

Answer 7

what was done wrong is that Nakim added the 3+2-15 = -10
and you can not add the 2x because of the variable, can only be added the
3 -15

Answer 8

so the answer on this would be
-12\(\sqrt{2x}\) +2x \(\sqrt{2x}\)

Answer 9

im sorry but can you show me how you got the answer

Answer 10

I showed you, where is the part you don't understand so I can explain

Answer 11

how sid you get the answer

Answer 12

?

Answer 13

im not good with these so can you possibly show me step by step how you got the answer

Answer 14

3 \(\sqrt{2x}\) + x \(\sqrt{4.2x}\) -5\(\sqrt{9.2x}\)

Answer 15

are you good up to there

Answer 16

I got it Nakim started out correct but on the last step he combined all three terms when only the first and last terms can be combined. The middle term, 2x*SQRT(2x), cannot be combined with the other two.

2. 3SQRT(2x) + xSQRT(8x) - 5SQRT(18x)
= 3SQRT(2x) + xSQRT(4)SQRT(2x) - 5SQRT(9)SQRT(2x)
= 3SQRT(2x) + x*2SQRT(2x) - 5*3SQRT(2x)
= 3SQRT(2x) + 2xSQRT(2x) - 15SQRT(2x)
= -12SQRT(2x) + 2xSQRT(2x)

or [SQRT(2x)]*[-12+2x]