Area and perimeter of figures on grids

Key Notes :

📏 Area and Perimeter of Figures on Grids

1️⃣ What is Perimeter?

Definition: Perimeter is the total distance around a figure.

How to find: Add the lengths of all sides.

Example:

A rectangle on a grid with sides 4 units and 3 units:

• Perimeter = 4 + 3 + 4 + 3 = 14 units ✏️

Tip: Count squares along the boundary if sides are on a grid. 🟦

---

2️⃣ What is Area?

Definition: Area is the amount of space inside a figure.

How to find: Count all the squares inside the shape on the grid. 🟩

Formula for common shapes:

• Rectangle → Area = length × width
• Square → Area = side × side

Tip: Each small square on a grid usually represents 1 unit².

---

3️⃣ Using Grids to Measure

Grid lines help:

• Count the number of squares inside → Area
• Count the squares around the edges → Perimeter

Shortcut: For rectangles & squares, use formulas instead of counting every square. 🧮

---

4️⃣ Irregular Shapes

• Break the shape into smaller rectangles or squares, find area of each part, and then add them together.
• For perimeter, trace the outline along the grid squares and sum the lengths. 🔄

---

5️⃣ Tips & Tricks 💡

• Color the squares inside a shape to count area easily. 🎨
• Use a ruler or unit squares to measure the length of sides for perimeter. 📏
• Double-check: Make sure each side is counted only once for perimeter! ✅

---

6️⃣ Fun Emoji Memory Aid

• 🟩 = square unit → area
• 📏 = ruler → perimeter
• ➕ = sum → add all sides or areas

Learn with an example

Let’s practice!🖊️