When we look at two-dimensional shapes, it's important to know about area and perimeter. These ideas help us understand how much space is inside a shape and how far it is around the shape. Let’s take a closer look at area and perimeter in a simple way.
Area tells us how much space is inside a shape. Different shapes have different ways to calculate the area:
Rectangle: To find the area, we use this formula:
Area (A) = length × width
For example, if a rectangle is 5 cm long and 3 cm wide, the area is:
A = 5 × 3 = 15 cm².
Triangle: The area is given by this formula:
Area (A) = ½ × base × height
If a triangle has a base of 4 cm and a height of 5 cm, the area is:
A = ½ × 4 × 5 = 10 cm².
Circle: To find the area, we use:
Area (A) = π × r²
Here, r is the radius. For a circle with a radius of 2 cm, the area is about:
A ≈ 3.14 × 2² = 12.56 cm².
Perimeter tells us the total distance around a shape. Like area, different shapes use different formulas for perimeter:
Rectangle: The formula is:
Perimeter (P) = 2 × (length + width)
For the rectangle we talked about earlier, the perimeter is:
P = 2 × (5 + 3) = 16 cm.
Triangle: To find the perimeter, just add up the lengths of all three sides:
Perimeter (P) = side₁ + side₂ + side₃
Circle: The distance around a circle is called circumference, and we find it with:
Circumference (C) = 2 × π × r
Knowing about area and perimeter helps us understand math in real life. For example, we can calculate how much paint we need for a wall or how much fencing to buy for a garden. Learning these concepts helps us better understand two-dimensional shapes and improves our geometry skills.
When we look at two-dimensional shapes, it's important to know about area and perimeter. These ideas help us understand how much space is inside a shape and how far it is around the shape. Let’s take a closer look at area and perimeter in a simple way.
Area tells us how much space is inside a shape. Different shapes have different ways to calculate the area:
Rectangle: To find the area, we use this formula:
Area (A) = length × width
For example, if a rectangle is 5 cm long and 3 cm wide, the area is:
A = 5 × 3 = 15 cm².
Triangle: The area is given by this formula:
Area (A) = ½ × base × height
If a triangle has a base of 4 cm and a height of 5 cm, the area is:
A = ½ × 4 × 5 = 10 cm².
Circle: To find the area, we use:
Area (A) = π × r²
Here, r is the radius. For a circle with a radius of 2 cm, the area is about:
A ≈ 3.14 × 2² = 12.56 cm².
Perimeter tells us the total distance around a shape. Like area, different shapes use different formulas for perimeter:
Rectangle: The formula is:
Perimeter (P) = 2 × (length + width)
For the rectangle we talked about earlier, the perimeter is:
P = 2 × (5 + 3) = 16 cm.
Triangle: To find the perimeter, just add up the lengths of all three sides:
Perimeter (P) = side₁ + side₂ + side₃
Circle: The distance around a circle is called circumference, and we find it with:
Circumference (C) = 2 × π × r
Knowing about area and perimeter helps us understand math in real life. For example, we can calculate how much paint we need for a wall or how much fencing to buy for a garden. Learning these concepts helps us better understand two-dimensional shapes and improves our geometry skills.