2x^3 + x^2 - 4x - (9x^3 - 3x^2) =
2x^3 + x^2 - 4x - 9x^3 + 3x^2 =
-7x^3 + 4x^2 - 4x <===
At the 2/8 part, just use the quadratic formula. If you use it, you should get the other two zeroes:

Based on the given conditions, formulate:
If the fraction is defined, the denominator cannot equal 0.:
Append the inequality as the domain:
Reduce the fraction:
Multiply both sides of the equation by the common denominator:
Reduce the fractions:
Swap the sides:
Divide both sides of the equation by the coefficient of variable:
Cross out the common factor:
Find the intersection:
get the result:
Answer: x=560
Answer:
See below.
Step-by-step explanation:
$32/( 2 hours) = $16/hour
A) $16/hour * 8 hours = $128
B) $16/hour * 20 hours = $320
C) $32/(2 hours) = $16/hour