find the

Ex: Find the Square Footage of a House

We want to determine the square footage of the house without the garage,

and with the garage.

To determine the square footage of a house we want to determine

the area of the floor space. To do this we'll be using the area formula for our

rectangle, where the area is equal to length times width.

If this is our rectangle, we could call this the length and this the width.

So there's a couple ways of doing this. We could divide this up into small rectangles and

then determine the area of each rectangle.

But I think it will be easier if we determine the area of this large rectangle,

and then subtract out the area of this small rectangle here,

and this small rectangle here.

And this would give us the area of the house without the garage.

So looking at this side of the blue rectangle,

from here to here is forty feet, but from here to here

would be the same as this length here, so this is six feet.

So this entire side would be forty-six feet. Then looking at this

side down here, from here to here is twenty-two feet.

But again, since this is eight feet here,

this segment here would also be eight feet,

so this side is forty-six feet long for the blue rectangle,

and this side of the rectangle would be thirty feet.

So for the area of the house without the garage, we'll call it area one, we're going

to have the area of this blue rectangle, which would be forty-six times thirty.

And then we're going to subtract out the area of this small orange rectangle,

which would be eight times six. And then we'd also subtract out the area of this

rectangle here, which is twenty-four feet by eight feet, so the area is twenty-four times eight.

So forty-six times thirty

is one thousand, three hundred eighty.

Eight times six is forty-eight and twenty-four times eight is one hundred ninety-two.

So this gives us one thousand, one hundred forty, and this would be square feet

for the area of the house without the garage.

It is also referred to as the square footage of the house.

Now to determine the square footage of the house with the garage, we'll call it area sub-two.

We'll take the area of the house and add the area of the garage.

Well this garage is eighteen feet by twenty-two feet,

so the area would be eighteen times twenty-two.

So we have one thousand, one hundred forty plus eighteen times twenty-two is three hundred ninety-six.

This is equal to one thousand, five hundred, thirty-six square feet,

which would be the square footage if we include the garage,

which is the same as the area.

And that'll do it for this example.