Four friends will build a model castle. The castle will have 4 walls made of 20 blocks each and 4 towers made of 5 blocks each. Each friend described a way
to find the total number of blocks needed to build the castle, as shown below.
• Gordon: “Add 20 and 5, and then multiply that sum by 4."
• Kate: "Add 4 and 5, and then multiply that sum by 20."
• Selena: "Multiply 4 and 5. Multiply 4 and 20. Then add those 2 products
together."
• Thomas: "Add 20, 4, and 5, and then multiply that sum by 4."
Which 2 friends wrote correct expressions?

An energy plant is looking into putting in a system to remove harmful pollutants from its emissions going into earth's atmosphere. the cost of removing the pollutants can be modeled using the function c = 25000p/100 -p what is the vertical asymptote?

If x-1 and x+3 are the factors of x3+10x2+ax+b find a and b

Mrs. julien’s and mrs. castillejo’s classes are selling cookie dough for a school fundraiser. customers can buy packages of macadamia nut chip cookie dough and packages of triple chocolate cookie dough. mrs. julien’s class sold 25 packages of macadamia nut chip cookie dough and 30 packages of triple chocolate cookie dough for a total of $221.25. mrs. castillejo’s class sold 5 packages of macadamia nut chip cookie dough and 45 packages of triple chocolate cookie dough for a total of $191.25. (a) write the system of equations that model the problem. be sure to explain which equation represents which situation. (b) find the cost of each type of cookie. show your work. (c) explain which method you used to solve the system and why you chose that method.