Demi is working on a presentation about a famous mathematician for her math class. She decides to make her poster in the shape of a plus sign.

The question is incomplete. The complete question is:

Demi os working on a representation about a famous mathematician for her math class. She decides to make her poster in the shape of a plus sign. What is the total area of Demi's poster? The image and the measurements of the poster are in the attachment.

Total area = 1360 square inches

Step-by-step explanation: From the attachment, the poster is formed by two rectangles one over the other and a central part, which is a square. So, the total area is the area of the 2 rectangles minus the area of the square

A = Ar - As

As these forms are regular, the area of both is A = width * length

Area of the 2 rectangle:

width = 20 in

length = 12+20+12 = 44 in

There are 2, then:

Ar = 2.20.44

Ar = 1760

Area of the square:

width = length = 20

As = 20²

As = 400

Total Area:

At = Ar - As

At = 1760 - 400

At = 1360

The total area of the poster is 1360 square inches.

a c

step-by-step explanation: