X^4-3x³+4x
x^4-3x³+3x+x
(x^4+x)-(3x³-3x)
x(x³+1)-3x(x²-1)
x(x+1)(x²-x+1)-3x(x+1)(x-1)
x(x+1)(x²-x+1-3x+3)
x(x+1)(x²-4x+4)
x(x+1)(x-2)(x-2)
so x intercepts are (0,0), (-1,0) and (2,0)
the y intercept is (0,0)
Xy is the number
A) x + y = 7
B) 10y + x = 10x + y + 9
collecting terms of equation B
B) -9x + 9y = 9
multiplying A) by 9
A) 9x + 9y = 63 then adding it to equation B)
B) -9x + 9y = 9
18y = 72
y = 4
x = 3
The number is 34
X +(1/x) = -0.5 has no real solutions.
There are no real numbers that meet your requirements.
_____
The two complex numbers that meet your requirement are
-1/4 +i√(15/16), -1/4 -i√(15/16)