Orchid wants to retile her bathroom floor, which has an area of 40 square feet. she is deciding between two types of custom tiles. the square tile is    foot by    foot and costs $0.45 per tile. the rectangular tile is 2 feet by    foot and costs $0.80 per tile. which tile should orchid choose to minimize costs? explain.

To find this its quite simple so bear with me,

Her floor is 40 square feet in area.

We have a tile that is 1 by 1 square feet and is 0.45$ per tile
Lets do that math

40 square feet and 1 by 1 tiles for 0.45 each

So lets do 40 x 0.45 to find the price for that

That will cost her 18.00$ for the 1 by 1 for 0.45$ each

Now lets work on her second option

Her floor is still 40 square feet in area.

But now she has a 2 by 2 tile for 0.80 per tile
Lets do that math

So the last tile we did was 1 by 1 so we did 40, which was he total tile area.
But now we have 2 by 2. 

So instead of 1 by 1 being 40 lets do 2 by 2 and divide 40 by 2 for the 2 by 2 tiles.

40 divided by 2 is 20.

So now we take her 20 tiles she can fit on her 40 square foot floor since the tiles are 2 by 2.
(You can do this backwards and make sure this is right. 20 x 2 = 40)

And we do 20  x 0.80 and we get 16.00$

So now we have both options
The 1 by 1 for 0.45 being 18.00$
The 2 by 2 for 0.80 being 16.00$

So now we can come to the conclusion that the second option being 2 by 2 for 0.80 each being 16.00$ is cheaper.

Hope this helps!
Brainliest is always appreciated if you feel its deserved! :)

Ive seen this before! the answer is b