Ms. Smith has decided to open a hot dog stand. She has found that her daily costs are approximated by the following equation: C(x) = x2 – 40x + 610. C(x) is the cost in dollars to sell x hot dogs.
a) Find the number of hot dogs she must sell to minimize her cost. ________
b) Find that minimum cost. _______________
c) What is Ms. Smith’s beginning cost each day for the hot dog stand? __________________

Question

Ms. Smith has decided to open a hot dog stand. She has found that her daily costs are approximated by the following equation:   C(x) = x2 – 40x + 610.  C(x) is the cost in dollars to sell x hot dogs.
a)  Find the number of hot dogs she must sell to minimize her cost.  ________
b)  Find that minimum cost.  _______________
c)  What is Ms. Smith’s beginning cost each day for the hot dog stand?  __________________

1645323 · Answer

@AravindG @skullpatrol @AnswerMyQuestions @greenlegodude57

1645323 · Answer

@phi @OneRepublic @crabby_patty

1645323 · Answer

is the beginning cost 610?

anonymous · Answer

Not sure. Sorry.

phi · Answer

The cost is the equation
 C(x) = x^2 – 40x + 610

that is the equation of a parabola with a U shape.  Its vertex (at its bottom) is the minimum cost.

do you know how to find the x value of the vertex of the equation
y= a x^2 + bx + c
?
it is when x= -b/(2a)