Question

Im stuck in this problem who knows how to solve this? cube root of..xsqr+6x=3..see drawing please

Answer 1

Good so far, you've cubed both sides, which gives you what?

Answer 2

i dont know???how do you cube the left side??

Answer 3

When you cube a cube root, they both effectively cancel each other out (since one undoes the other). This means that the cube root goes away on the left side

Answer 4

Leaving you with x^2 + 6x on the left side

Answer 5

so cube the right side, 3, to get 3^3 = ???

Answer 6

very close, but 3^3 (three cubed) is NOT the same as 3^2 or 3*3


3^3 = 3*3*3 = 9*3 = 27


So 3^3 = 27

Answer 7

so you'll now have x^2+6x = 27, you can then subtract 27 from both sides to get


x^2+6x - 27 = 0

Answer 8

haha oh ok got distracted and then factor that???

Answer 9

yes exactly

Answer 10

Good job. Those are the answers to x^2+6x - 27 = 0

But they aren't guaranteed answers to the original equation. What you need to do from here is plug each answer (separately) into the original equation and simplify. If you get a true equation, then it will verify the potential solution.

Answer 11

thank you! ill check them

Answer 12

You're welcome, usually it's a good idea to check any and all answers, but it's especially important when dealing with radical equations.

Answer 13

yess ill have that in mind...thanks !