write the area if x=9

Question

the length of the office is x feet and the width is x + 3. write the polynomial that represents the area. Find the area if x=9.

Answer 1

Area of a rectangle is written as

 

A = L * W

 

We know the length is x

We know the width is (x + 3)

 

Plug both into the equation above.

 

A = (x)(x+3)

 

Simplify

 

A = x² + 3x  === Equation for Area

 

We also know that x = 9. We will now substitute 9 in for x and get:

 

A = (9)²+(3*9)

A = 81 + 27

A = 108

 

We do not know the units as they are not specified, but make sure you put in the units as well.

Answer 2

area=length times width.

 

So here it's area=9*(9+3)=9*12=108 ft^2

Answer 3

Assuming the office is in the shape of a rectangle, the area of a rectangle is length times width:

 

A = lw

 

If the length is x, and the width is x + 3, then the area can be re-expressed as:

 

A = x (x + 3)

A = x² + 3x

 

When the length is 9:

A = x² + 3x

A = 9² + 3(9)

A = 81 + 27

A = 108

 

If desired you can double check as follows. If the length is 9, then the width is 9 + 3, or 12. Area is length times width, which is 9 x 12, which is indeed 108.

 

Answer 4

The area of a rectangle is defined as Area = Length multiplied by width.

 

The length of the rectangle has been defined by the variable x. So substitute.

 

The area is Area = x * (x+3)

 

When x = 9, as in the problem, the area is = 9 * (9+3) = 9*12 = 108 square feet.