Generate a video to teach an 11-year student in Singapore about areas of a triangle. Show different scenarios of how to calculate triangle areas like find the shaded area, what it the height or base of the triangle if X area is shaded or Y height is. Ensure it follows the Singapore PSLE curriculum/syllabus.

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Welcome to our lesson on the area of a triangle! The area of a triangle is the amount of space inside the triangle. To calculate it, we use a simple formula: Area equals one-half times the base times the height. The base is any side of the triangle, and the height is the perpendicular distance from the base to the opposite vertex. Remember, the height must be perpendicular to the base, forming a right angle. Let's work through an example. We have a triangle with a base of 6 centimeters and a height of 4 centimeters. To find the area, we use our formula: Area equals one-half times base times height. Substituting our values, we get one-half times 6 centimeters times 4 centimeters. This gives us one-half times 24 square centimeters, which equals 12 square centimeters. So the area of our triangle is 12 square centimeters. Now let's try a different type of problem. If we know the area of a triangle and its height, we can find the base. Here's our problem: A triangle has an area of 24 square centimeters and a height of 8 centimeters. What is the base? We start with our formula: Area equals one-half times base times height. To find the base, we rearrange the formula: base equals 2 times area divided by height. Substituting our values, we get base equals 2 times 24 square centimeters divided by 8 centimeters. This gives us 48 square centimeters divided by 8 centimeters, which equals 6 centimeters. So the base of our triangle is 6 centimeters. Now let's look at a common problem type: finding the area of a shaded region. In this example, we have a triangle inside a rectangle. The rectangle has dimensions 8 centimeters by 6 centimeters, and the triangle is formed by connecting the bottom-left corner, the top-right corner, and the bottom-right corner of the rectangle. To find the shaded area, we subtract the area of the triangle from the area of the rectangle. The area of the rectangle is 8 centimeters times 6 centimeters, which equals 48 square centimeters. The area of the triangle is one-half times 8 centimeters times 6 centimeters, which equals 24 square centimeters. Therefore, the area of the shaded region is 48 square centimeters minus 24 square centimeters, which equals 24 square centimeters. Let's summarize what we've learned about the area of triangles. First, the area of a triangle is one-half times the base times the height. Remember that the height must always be perpendicular to the base. If we know the area and either the base or height, we can find the missing dimension by rearranging the formula. For problems involving shaded regions, we can add or subtract the areas of different shapes as needed. And finally, always remember to include the correct units in your answer, such as square centimeters or square meters. These concepts will help you solve many different types of triangle area problems in your PSLE exam.