The walls in a room are being painted. four cans of paint will cover 480ft 2. how many cans will be needed to cover 840ft2

  7 cans

Step-by-step explanation:

The number of cans of paint is presumed to be proportional to the area, so ...

  (4 cans)/(480 ft²) = (how many cans)/(840 ft²)

Multiplying by 840 ft², we get ...

  (how many cans) = (4 cans)(840 ft²)/(480 ft²) = (4 cans)(7/4)

  (how many cans) = 7 cans

step-by-step explanation:

the answer is (4,3)

since the rule for r0, 90º is (-y,x) and it was already applied to form the image, all you have to do is reverse the answer using this formula.