Geometry Vocabulary
What do we call the amount of space inside a flat shape, measured in square units?
Area
What is the formula for the area of a parallelogram?
A = b × h
What is the formula for the area of a triangle?
A = (b × h) ÷ 2
You cut a shape into pieces and rearrange all the pieces without gaps or overlaps. Does its total area change?
No. The same pieces cover the same total area.
How many squares make up the net of a cube?
6 squares
What is the name of a quadrilateral with two pairs of parallel sides?
Parallelogram
A parallelogram has a base of 7 cm and a matching height of 4 cm. What is its area?
28 cm²
A triangle has a base of 10 cm and a matching height of 4 cm. What is its area?
20 cm²
A shape is divided into two non-overlapping rectangles with areas of 15 cm² and 12 cm². What is the total area?
27 cm²
A square pyramid has one square face with an area of 16 cm² and four triangular faces with an area of 6 cm² each. What is its surface area?
40 cm². Calculate 16 + 4 × 6.
A height must be perpendicular to its matching base. What angle do they form?
A right angle, or 90°
A parallelogram has a base of 9 m, a slanted side of 6 m, and a perpendicular height of 4 m. What is its area?
36 m². Use 9 × 4.
A triangle has a base of 7 m and a matching height of 5 m. What is its area?
17.5 m²
A 3 cm by 2 cm rectangle is cut out of an 8 cm by 5 cm rectangle. What area remains?
34 cm². Calculate 40 − 6.
A cube has an edge length of 4 cm. What is its surface area?
96 cm². Each face is 16 cm²; 6 × 16 = 96.
What do we call a flat arrangement of polygons that can fold into a three-dimensional figure?
A net
A parallelogram has an area of 54 cm² and a base of 9 cm. What is its matching height?
6 cm. Calculate 54 ÷ 9.
A triangle has an area of 36 cm² and a base of 9 cm. What is its matching height?
8 cm. Calculate 36 × 2 ÷ 9.
A house-shaped figure consists of a rectangle and a triangular roof with no overlap. The rectangle is 6 m wide and 4 m tall. The triangle has a base of 6 m and a height of 3 m. What is the total area?
33 m². Rectangle: 24; triangle: 9.
A rectangular prism is 5 cm long, 3 cm wide, and 2 cm tall. What is its surface area?
62 cm². Calculate 2 × 15 + 2 × 10 + 2 × 6.
You are wrapping a box and then filling it. Which measurement tells you how much paper covers the box, and which tells you how much space is inside?
Surface area tells how much paper covers it; volume measures the space inside.
A parallelogram has a base of 8 cm and a height of 5 cm. A second parallelogram has the same area and a base of 10 cm. What is the second parallelogram’s height?
4 cm. The area is 40 cm²; 40 ÷ 10 = 4.
A triangle and a parallelogram both have a base of 12 cm and a height of 5 cm. What is each area, and how do they compare?
Triangle: 30 cm². Parallelogram: 60 cm². The triangle has half the area
A 10 m by 8 m rectangular garden has a 4 m by 3 m rectangular pond inside it. The rest is covered with grass. If grass costs $2 per square meter, what is the total cost?
$136. Grass area: 80 − 12 = 68 m²; 68 × $2 = $136.
An open-top rectangular box is 10 cm long, 6 cm wide, and 4 cm tall. What is the total area of its bottom and four sides?
188 cm². Calculate 60 + 40 + 40 + 24 + 24.