x + 2 is a factor of V(x) = x³- 10x²+ 11x + 70; and x = -5 is not a possible rational zero.
A cubic equation is a polynomial of degree 3.
Given the volume (V) is given by:
V(x) = x³- 10x²+ 11x + 70; where x is the length of the hot tub
a) x cannot be -5 because we cannot have a negative length, also:
V(-5) = (-5)³- 10(-5)²+ 11(-5) + 70 = -360; Also the volume cannot be negative.
b) x + 2 is a factor, hence:
x + 2 = 0
x = -2
v(-2) = (-2)³- 10(-2)²+ 11(-2) + 70 = 0
x + 2 is a factor of V(x) = x³- 10x²+ 11x + 70; and x = -5 is not a possible rational zero.
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