PLEASE HELP Select the correct answer from each drop-down menu.
8 cm
4 cm
9 cm
3 cm
3 cm
6 cm
The given composite shape has an area of
cm² and a perimeter of
cm.

Answers:

Area = 78 cm^2

Perimeter = 42 cm

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Explanation:

Refer to the diagram below.

I've added points and labels, along with the dashed lines to break up the figure into three rectangles. The points in blue are the corner points of the original figure. The red points help set up the dashed lines.

Along the very top, we have BC = 8 cm, which breaks down into BK = 6 and KC = 2. Opposite of side KC is GJ = 2. For any rectangle, the opposite sides are always the same length.

Side AB = 9 cm. The three vertical sides of CD, EF, and GH all must add to get 9 cm in total, since the right side is the same height as the left side. We are given that EF = 3 and GH = 3, which must mean CD = 3 as well.

Through similar logic, the sides BC = 8 and DE = 4 add to 8+4 = 12 cm total. This total distance across the top must match the total distance along the bottom; i.e. the bottom horizontal sides of AH and GF must add to 12 as well. We are given AH = 6, so GF = 6 also.

Recall earlier we found GJ = 2. If GF = 6, then that leads to JF = 4.

In other words, GJ+JF = 2+4 = 6 = GF.

All of this is visually shown in the diagram shown below.

Once you have the diagram set up as shown, it's fairly straight forward from here. Compute the area of each of the three smaller rectangles and then add up those smaller areas to get the overall area.

I'll work from left to right to find the areas:

The total area of the composite figure is therefore: 54+12+12 = 78 cm^2

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The perimeter is the sum of all the external sides. We'll ignore the dashed lines as they are not exterior segments.

perimeter = sum of exterior sides

perimeter = AB+BC+CD+DE+EF+FG+GH+HA

perimeter = 9+8+3+4+3+6+3+6

perimeter = 42 cm

Notes:

.mp4 files, because, video

in problems involving proportions, we can use cross products to test whether two ratios are equal and form a proportion. to find the cross products of a proportion, we multiply the outer terms, called the extremes, and the middle terms, called the means.

hope it