Question

I've worked through this over and over again and still can't figure it out can someone help?
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

\[3\sqrt{2x}+x \sqrt{8x}-5\sqrt{18x}\]

Answer 2

and he got \[-10x \sqrt{2x}\]

Answer 3

I see what he did.
If you simplify that 2nd term you get 2xsqrt(2x)
1st term doesn't simplify
Last term simplifies to -15sqrt(2x)
You can combine the first and last terms, but you have to leave the 2nd term separate because of that x in front of the square root. Nakim ignored the x

Answer 4

thank you so much!!

Answer 5

sure, no problem!

Answer 6

\(\bf 3\sqrt{2x}+x \sqrt{8x}-5\sqrt{18x} \implies 3\sqrt{2x}-5\sqrt{18x}+\color{red}{x \sqrt{8x}}\)

Answer 7

so like bangkokGarrett said, he ignored the x

Answer 8

yes