Is x-8 a factor of the function f(x)=-2x^3+17x^2-64?Explain

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  yes

Step-by-step explanation:

x-8 will be a factor if f(8) = 0.

f(8) = -2(8^3) +17(8^2) -64 = 64(-16 +17 -1) = 0

Yes, x-8 is a factor.

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.