Decompose Shapes for Area

What is the proper way to get the area of an irregular polygon (also known as a composite figure)?

• Decompose it into known shapes and get the area of each shape. Subtract those areas from each other to get the total area.

• take a guess

• Decompose it into known shapes and get the area of each shape. Add those areas to each other to get the total area.

• Decompose it into known shapes and get the area of each shape. Multiply those areas by each other to get the total area.

Tags

CCSS.3.MD.C.7D

This is the formula to find the area of which shape?

• parallelogram

• triangle

• square

• trapezoid

Tags

CCSS.6.G.A.1

___________ means “take apart.” We use this word to describe taking a figure apart to make more than one new shape

• Compose

• Area

• Decompose

• Volume

Tags

CCSS.1.G.A.2

Find the area of the composite figure.

• 19 square cm

• 30 square cm

• 29 square cm

• 45 square cm

Tags

CCSS.3.MD.C.7D

Decompose the irregular shape and find its total area.

• 96 units2

• 152 units2

• 192 units2

• 240 units2

Tags

CCSS.3.MD.C.7D

Find the area of the composite figure.

___ square feet

Tags

CCSS.3.MD.C.7D

Find the area of the composite figure.

• 19 square cm

• 30 square cm

• 29 square cm

• 45 square cm

Tags

CCSS.3.MD.C.7D

Decompose the trapezoid into a rectangle and two right triangles. What is the area of this trapezoid?

• 45 ft²

• 72 ft²

• 57 ft²

• 40 ft²

Find the area of the composite figure.

___ square centimeters

Tags

CCSS.3.MD.C.7D

Select all the true statements about this shape (Hint: Select all means more than one)

• The area can be found by decomposing into rectangles

• The area cannot be found because there are too many measurements

• The area can be found by multiplying 60x30 and subtracting missing pieces

• The area can be found by adding all the side lengths together