A regular polygon can be split into equal triangles, so you find one triangle's area and multiply by how many triangles there are. That runs on triangle area (base × height ÷ 2), multiplication facts, and adding equal areas. Warm those up and a hexagon is just six triangles.
Answer these 3, then press Show my path. No grade — this just points you to the right level.
1. A triangle has base 4 and height 3. Its area is base × height ÷ 2 = ?
2. What is 6 × 5?
3. Six triangles each have area 4. What is the total area?
A regular polygon has all sides and angles equal. Draw lines from the center to each corner and it breaks into equal triangles. Find one triangle's area, then multiply by the number of triangles (or add them up — same thing).
Your quick check picks one for you, but you can switch any time:
Level 0 Find one triangle, then count copies.
A. A triangle has base 4 and height 2. Find base × height: 4 × 2 = ___?
4 × 2 = 8.
B. Take half of 8 to get one triangle's area: ___?
8 ÷ 2 = 4 square units.
C. There are 3 of those triangles. Total = 3 × 4 = ___?
3 × 4 = 12 square units.
Level 1 Multiply one triangle by the number of triangles.
A. One triangle is 5 sq units. A pentagon has 5 of them. Total = 5 × 5 = ___?
5 × 5 = 25 square units.
B. One triangle is 6 sq units. A hexagon has 6 of them. Total = 6 × 6 = ___?
6 × 6 = 36 square units.
Level 2 Stretch: build one triangle, then the whole polygon.
A. A triangle has base 6 and height 4. Its area is base × height ÷ 2 = ___?
6 × 4 = 24, half of 24 = 12 square units.
B. A hexagon is made of 6 such triangles. Total = 6 × 12 = ___?
6 × 12 = 72 square units.
1. A triangle has base 5 and height 4. Find base × height ÷ 2: ___?
5 × 4 = 20, half of 20 = 10 square units.
2. Five equal triangles each have area 10. What is the total area?
5 × 10 = 50 square units.
You've practiced exactly what Lesson 5-4 uses. Time to dive in.
Start Lesson 5-4 →