Question

factor the expression
3
2x + 54 = 0 (the x is cubed)

Answer 1

First we guess for one factor, I guessed and found that x-3 is a factor cause when x=3, the equation is equal to 0.

Answer 2

x = -3 is the correct answer.

Answer 3

I tried to get tutored and could not get help at school. I am not sure how yall got the answer.

Answer 4

it isnt the final answer though u still have to use remainder factor theorem to get the other two factors

Answer 5

\[2.x ^{3}+54 = 0\]
\[2.x ^{3}= -54\]
\[x ^{3} = -27\]
\[x ^{3}= -3*-3*-3\]
\[x^{3} = -3^{3}\]
x = -3

Answer 6

while sandeep gets the other factors i can help u to under stand this first part

Answer 7

Hey Hawkson, just recheck, for x = 3 the equation doesnt satisfies.

Answer 8

I appreciate the help. I am in pre algebra in college. our professor blew through this in 10 mins and I am so lost.

Answer 9

Is that clear to you now!? Janedoepcola?

Answer 10

but when i expand it i dont get back the original 2x^3 + 54 = 0
I get x^3 + 9x^2 + 27x + 27

Answer 11

u understand it?

Answer 12

Yeah, Because what you have done is \[(x+3)^{3}\]
but actually it is in the form \[2*(x^{3}-(-3)^{3})=0\]

Answer 13

When you factor out a 2, you end up with 2(x^3 +27)=0 You have to recognize x^3+27 as a sum of two cubes. The sum of two cubes factors as follows:

\[x ^{3}+a ^{3}=(x+a)(x ^{2}-ax+a ^{2})\]