If you know the diameter of a circle, which statement describes how to find the area?
a) multiply the diameter by π.
b) square the diameter and multiply by π.
c) divide the diameter in half and multiply by π.
d) divide the diameter in half, square, and multiply by π.

c

Step-by-step explanation:

PI times radius squared

d

Step-by-step explanation: The formula for area of a cicle is a=pi(r^2). I like to remember circumference and area by the sentence cherry pies are delicious, apple pies are too. (c[herry]=pi*d, a[pple]=pi(r^2)

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: