Giuseppi's pizza had orders for $931.00 of pizzas. the prices were $21 for a large pizza, 514 for a medium pizza, and $7 for a small pizza. the number of large pizzas was two less than four times the number of medium pizzas. thenumber of small pizzas was three more than three times the number of medium pizzas. how many of each size of pizza were ordered?

Number of Large Pizzas: 30

Number of Medium Pizzas: 8

Number of Small Pizzas: 27

Step-by-step explanation:

L = # of large Pizzas

M = # of medium Pizzas

S = # of small Pizzas

Amount:

L = 4M - 2

S = 3M + 3

Cost:

21L + (I'm assuming you meant 14) 14M + 7S = 931

Plus in the Amounts to the Cost:

21(4M - 2) + 14M + 7(3M + 3) = 931

84M - 42 + 14M + 21M +21 = 931

Combine like terms:

119M - 21 = 931

Isolate the Variable:

119M - 21 + 21 = 931 + 21

119M = 952

119M/119 = 952/119

M = 8

Plug it into the Amount equations:

Large: L = 4(8) - 2

L = 32 - 2

L = 30

Small: S = 3M + 3

S = 3(8) + 3

S = 24 + 3

S = 27

Check your work (plug the values into Cost.):

21(30) + 14(8) + 7(27) = 931

630 + 112 + 189 = 931

931 = 931

so, to find the x intercept, we want f(x)=0. that instantly gives us cos(x+3)=0 bbecause 2 equal 0. cos(x+3) equals 0 when:

we also know that the arccosine of 0 is , meaning we are looking for the decimal approximation of: , which is -1.42920367, and when rounded to two decimal places it is -1.429