The cost of fixing errors in a computer program is related to the time spent developing the program by the equation y = 4x - 2,000x + 8,000, where x = the
time in hours and y = the cost in dollars. Which best describes the meaning of the
vertex of the parabola with that equation?
The cost reaches a maximum when 500 hours are spent developing the program.
The cost reaches a minimum when 500 hours are spent developing the program.
The cost reaches a minimum when 250 hours are spent developing the program.
The cost reaches a maximum when 250 hours are spent developing the program.

x^3-4x^2+3x-2/x^2+1

step-by-step explanation:

factor the numerator and denominator and cancel the common factors

proportions are fractions that equal to each other. so if two fractions are the same, they are proportional.

let's check the answers to see if they are proportional.

question a is not proportional because you can't turn 1.5/3 to 3/9. if you try to multiply 1.5/3 by 2 or 3, you wont get 3/9. it's impossible to make the fractions the same.

question b is not proportional because you can't turn 22/33 to 4/6. 33 can't go into 6.

question c is proportional because when you multiply 2 and 3 by 71, you would get 142/213, and those fractions equal to each other

question d is proportional because when you divide 14 and 7 by 2, you would end up with 7/3.5, and those fractions equal to each other.