Classrooms on one side of the science building are all numbered with consecutive odd integers. If the first room, the room with the smallest classroom number, on this side of the building is numbered k, write an expression in k for the sum of the first five classroom numbers in a row. Then simplify this expression. The sum of the first five classroom numbers in a row is

The sum of the first five classroom numbers in a row is 5k + 20

Step-by-step explanation:

Since the smallest classroom number on the side of the building is numbered k and each consecutive odd integer is separated by a difference of  

2.

Therefore:  

k is the first class room.

k +  2  is the second class room.

k +  4  is the third class room.

k + 6 is the third class room.

k + 8 is the fifth class room.

The sum of the five consecutive class rooms are given as:

k + (k + 2) + (k + 4) + (k + 6) + (k + 8)

collecting alike terms we get

=  k + k + k + k + k + 2 + 4 + 6 + 8

= 5k + 20

Therefore, The sum of the first five classroom numbers in a row is 5k + 20.

2 and 1.

step-by-step explanation:

plug in each answer. 0 doesn't work, 1 does. so does 2. 4 doesn't:

0 = 1 is not true.

2 = 2 is true.

4 = 4 is true.

8 = 16 is not true.

hope this !

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations: