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

can someone please help me I am trying to finish my online course with an a and am stuck on this problem

Answer 2

@Jim766 please help

Answer 3

\[3\sqrt{2x}+x \sqrt{8x}-5\sqrt{18x}\] sorry I screwed the 1st one up..lol

does this look right?

Answer 4

I think so I tried to figure it out but I have learning problems lol

Answer 5

lol...let see if we can figure it out. we need to simplify each term if we can

inside the radicals, I am looking for factors that are perfect squares, so when I square root them I get a number

Answer 6

\[3\sqrt{2x}+x \sqrt{4*2*x}-5\sqrt{9*2*x}\] the perfect squares are 4 and 9

Answer 7

\[3\sqrt{2x}+2*x \sqrt{2x}-5*3\sqrt{2x}\] when I take the sq root of the 4 and 9, I get this

Answer 8

\[3\sqrt{2x}+2x \sqrt{2x}-15\sqrt{2x}\] now that all the sq rts are the same I can combine like terms

Answer 9

\[3 -15+2x \sqrt{2x}\]

\[-12 + 2x \sqrt{2x}\]

Answer 10

now that is the correct answer, but they got \[-10x \sqrt{2x}\]
any idea what they did wrong?

Answer 11

they took -12 + 2x and got -10,

you cant do that because they are not like terms, you cant combine them.
that is why the correct answer leaves them separated.

Does that help any?

Answer 12

yes thank-you so like can you write it in the way of the question I cant get it right

Answer 13

3sqrt(2x) +xsqrt(8x) - 5sqrt(18x)

3sqrt(2x) +2xsqrt(2x) - 15sqrt(2x)

(-12+2x)sqrt(2x) this is simplified

Answer 14

thank-you soooooooo much!!!!!!