2x^4=-128x I did the problem but im getting the wrong answer.?

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answers:
Engr. Ronald say: 2x^4 = -128x
2x^4 + 128x = 0
2x(x^3 + 64) = 0
2x = 0, x^3 + 64 = 0
x^3 = - 64
x = cuberoot( - 64)
x = - 4 answer//
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JG say: Since you have a polynomial equation in one variable to the 4th degree, there's going to be four solutions.

2x^4=-128x
x^4=-64x
x^4+64x=0
x(x^3+64)=0
x(x+4)(x^2-4x+16)=0
x=0 or x=-4

x^2-4x+16=0
x^2-4x+4=-12
(x-2)^2 =-12
x-2 = +/−2i(3)^.5
x=2+/−2i(3)^.5

The roots are 0, -4, 2+/−2i(3)^.5
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marina say: 2x^4=-128x
Bring the two to the other side
x^4=-64x
bring the -64x to the other side so the equation equals 0
x^4 + 64x=0
Carry out as many x, as possible (in this case only 1)
x (x^3 + 64)=0
Find the zeros
x=0
&
x^3+64=0
bring 64 to the other side
x^3=-64
Find the cube root
x=-4

therefore x=0 OR x=-4
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lenpol7 say: Cancel down by 'x'
2x^3 = -128
x^3 = - 56
Cube root
x = +/- 56)^(1/3)
x = +/(- 2 x 2 x 2 x 7)^(1/3)
x = +/-2(7)^(1/3)
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Johnathan say: 2x^4 = -128x

2x^4 + 128x = 0

2x(x^3 + 64) = 0

2x(x + 4)(x^2 - 4x + 16) = 0

Case 1: 2x = 0 -> x = 0.

Case 2: x + 4 = 0 -> x = -4.

Case 3: x = (-(-4) +/- sqrt(4^2 - 4(1)(16))) / 2(1)

x = (4 +/- sqrt(16 - 64)) / 2

x = (4 +/- sqrt(-48)) / 2

x = (4 +/- 4i sqrt(3)) / 2

x = 2 +/- 2i sqrt(3).

4 solutions all told: x = 0, -4, 2 + 2i sqrt(3), or 2 - 2i sqrt(3).
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no sea nabo say: 2x⁴=-128x
2x(x³)=2x(-64)
x³=-64
x³=-(4³)
x=-4
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az_lender say: x could be 0. If not, then
x^3 = -64x, and x could be -4.
So the "real" roots are 0 and -4.
There are also two "complex" roots, namely,
x = -2 + 2i*sqrt(3) and
x = -2 - 2i*sqrt(3).
I don't know if your class has studied that?
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Alan say: add + 128x to both sides
2x^4 + 128x = 0
factor
2x*(x^3 +64) = 0
so x = 0 is one answer
x^3 +64= 0
x^3 = -64
take the cube root of both sides
x = cube_root(-64) = -4
so the answer are
0 and -4
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rotchm say: Show us what you did and we will show u where u erred.
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say: Divide each side by x

2x^3 = -128

x = -4
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? say: 2x⁴ = -128x

// Divide through by 2x to get
x³ = -64

x = ∛(-64)

x = ∛(-1 • 2³ • 2³)

x = 4 ∛(-1) ..................ANS
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