Aused electronics store pays $40 for each cell phone, spends $25 refurbishing the phone, and sells the refurbished phone to a customer  for $100. a.   write an expression in simplest form that represents the  company's earnings  (in dollars) from buying, processing, and selling cell phones. use x x   to represent the number of cell phones they sell. 

An equation of the line tangent to y=x^3+3x^2+2 at its point of inflection is

The swimming pool is open when the high temperature is higher than 20∘c. lainey tried to swim on monday and thursday (which was 3 days later). the pool was open on monday, but it was closed on thursday. the high temperature was 30∘c on monday, but decreased at a constant rate in the next 3 days. write an inequality to determine the rate of temperature decrease in degrees celsius per day, d, from monday to thursday.

What is the expression in factored form? -x^2 + 3x + 28 a. (x-7)(x-4) b. -(x-7)(x+4) c. (x+4)(x+7) d. -(x-4)(x+7)