Question

can someone help me figure this out step by step?: \[x ^{2}+(9\sqrt{3})^{2}=4x ^{2}\]

Answer 1

First share out the exponent to each of the terms in the parentheses..9^2*(sqrt3)^2

Answer 2

To get 81*3 = 243. ok with that step?

Answer 3

still there @pllfan ?

Answer 4

yup

Answer 5

okay with the first step?

Answer 6

done

Answer 7

Nice. so now it's 243 = 3x^2 Right?

Answer 8

yes

Answer 9

Wonderful. can u finish off from here?

Answer 10

um what happens after you divide 243 by 3

Answer 11

To get the value of x, you now get the sqrt of both sides of the equation. can u do that?

Answer 12

yes thank you

Answer 13

you're welcome. and do remember that your answer will be plusORminus (certain value).

Answer 14

is it both?

Answer 15

Just a sec. Sorry, no. take the positive value. The rules are,
sqrt of a known number = positive value e.g. sqrt(4) = 2
sqrt of an unknown number = positive/negative e.g. sqrt(x^2) = +x and -x
Hope that helps.

Answer 16

wait in what situatuon could you use the plus-minus sign?