Question 5 - Figure it out (Page 162-164) - Area of Parallelogram - Chapter 7 Class 8 - Area (Ganita Prakash II)

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Question 5 - Figure it out (Page 162-164) Give a method to obtain a rectangle whose area is twice that of a given triangle. What are the different methods that you can think of?We use two Methods . Let’s look at each in Detail Method 1 (Enclosure) In short, this method is Draw a horizontal line passing through the top tip (vertex) of the triangle, parallel to the base. Then, draw two vertical lines going straight up from the two bottom corners of the base until they hit that top line. You have now drawn a rectangle that completely boxes in your triangle. This rectangle has the same base and same height as the triangle, meaning its area is exactly twice as large! Now, let’s look at the 2nd method Method 2 (Duplication & Dissection) STEP 7 OF 8 The Resulting Rectangle The edges are now perfectly straight up and down. You have built a perfect rectangle using exactly two triangles' worth of material! Previous Next Step STEP 8 OF 8 The Base and Height Connection Look at the resulting rectangle. It has the exact same Base (bottom edge) and the exact same Height as our single original triangle. Since we used exactly two triangles to build this full Base-by-Height shape, the rectangle is naturally double the size! Previous Finish / RestartIn short, this method is Trace your given triangle and cut out an exact copy. Rotate that copy 180° and attach it to one side of the original triangle to form a parallelogram. Then, as shown on page 1 of your text, drop a perpendicular line to cut off a right-angled triangle from one end of the parallelogram, and move it to the other end to form a rectangle.