ClassX Video Lessons Youtube Channel Virtual Elementary School Grade 6 Math: Area of a Parallelogram and a Triangle
Have you ever wondered how to find the area of shapes like parallelograms and triangles? It’s easier than you might think, and you can use what you know about rectangles to help you!
Let’s start with a parallelogram. Imagine you have a shape that looks like a slanted rectangle. To find its area, you can use a neat trick. If you cut along one of its sides and slide a piece over, you can turn the parallelogram into a rectangle. Even though the shape changes, the area stays the same!
In a rectangle, you find the area by multiplying the length by the width. For a parallelogram, you do something similar: multiply the base (the bottom side) by the height (the straight line from the base to the top). So, if the base is 14 centimeters and the height is 10 centimeters, the area is 14 times 10, which equals 140 square centimeters. Easy, right?
Now, let’s talk about triangles. If you know how to find the area of a parallelogram, you can find the area of a triangle too! Here’s how: imagine making a copy of the triangle and putting the two triangles together. They form a parallelogram!
This new parallelogram has the same base and height as the original triangle. Since the area of the parallelogram is base times height, the area of one triangle is half of that. So, to find the area of a triangle, you multiply the base by the height and then divide by 2.
For example, if the base of the triangle is 14 centimeters and the height is 10 centimeters, you multiply 14 by 10 to get 140. Then, divide 140 by 2 to get 70 square centimeters. That’s the area of the triangle!
To sum it up, finding the area of these shapes is simple:
Now you can find the area of parallelograms and triangles with confidence. Keep practicing, and you’ll become a pro in no time!
Imagine you have a paper parallelogram. Cut along one side and slide the piece to form a rectangle. Measure the base and height, then calculate the area. Share your results with the class!
Draw a triangle on grid paper. Copy it and place the two triangles together to form a parallelogram. Measure the base and height, calculate the area of the parallelogram, and then find the area of the original triangle.
Work in teams to solve area problems for different shapes. Each team member calculates the area of either a parallelogram or a triangle. The first team to finish with correct answers wins!
Find objects around your home or school that resemble parallelograms and triangles. Measure their dimensions and calculate their areas. Present your findings to the class.
Use an online geometry tool to create parallelograms and triangles. Adjust the base and height, then calculate the area. Compare your answers with the tool’s calculations to see if they match.
Sure! Here’s a sanitized version of the YouTube transcript:
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How do we find the area of this parallelogram? We know how to find the area of a rectangle, and we can use that knowledge to find the area of a parallelogram. If we cut along this line and slide the triangle from one side of the parallelogram to the other, we can create a rectangle. We’ve transformed the parallelogram into a rectangle, but the area remains the same. The base and height of the parallelogram correspond to the length and width of the rectangle.
The area of a rectangle is calculated as length times width. This means that the area of this parallelogram is base times height. For example, 14 multiplied by 10 equals 140. Therefore, the area of this parallelogram is 140 centimeters squared. To find the area of a parallelogram, we multiply its base by its height.
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Now, how do we find the area of this triangle? Wait a second! We know how to find the area of a parallelogram, right? Let’s make an exact copy of the triangle and then put the two triangles together. We’ve created a parallelogram using two congruent triangles. This parallelogram has the same base and height as the triangle. The area of this parallelogram is base times height. This means that the area of the triangle is half as much.
The area of this triangle is calculated as base times height divided by 2. For instance, 14 times 10 equals 140, and 140 divided by 2 equals 70. Therefore, the area of the triangle is 70 centimeters squared. To find the area of a triangle, we multiply its base by its height and then divide by 2.
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Area – The amount of space inside a two-dimensional shape, measured in square units. – The area of the rectangle is 24 square centimeters.
Parallelogram – A four-sided shape with opposite sides that are parallel and equal in length. – To find the area of a parallelogram, you multiply the base by the height.
Triangle – A three-sided polygon. – The area of a triangle is calculated by multiplying the base by the height and then dividing by two.
Base – The bottom side of a shape, often used as a reference side for measuring height. – In a triangle, the base can be any one of its three sides.
Height – The perpendicular distance from the base to the top of a shape. – To find the area of a triangle, you need to know both the base and the height.
Rectangle – A four-sided shape with opposite sides that are equal and all angles that are right angles. – The area of a rectangle is found by multiplying its length by its width.
Centimeters – A metric unit of length, equal to one hundredth of a meter. – The sides of the square are each 5 centimeters long.
Multiply – To find the product of two numbers or quantities. – To find the area of a rectangle, you multiply the length by the width.
Divide – To split a number into equal parts or groups. – When you divide the area of a triangle by two, you find the correct area.
Shapes – Figures or forms such as circles, squares, triangles, and rectangles. – We learned about different shapes in geometry class today.
