Question 4 - Figure it out - Page 94 - Chapter 4 Class 8 - Quadrilaterals (Ganita Prakash)

Transcript

Question 4 We have seen how to get 90° using paper folding. Now, suppose we do not have any paper but two sticks of equal length, and a thread. How do we make an exact 90° using these? This uses the property that if the diagonals of a quadrilateral are equal and bisect each other, it is a rectangle. We follow these steps Gather Materials We have two sticks of length and a piece of thread. We need to create a right angle without a protractor. Back Next StepCross at Midpoints Mark the exact center of both sticks. Fasten them together at this point so they can rotate. Back Next Step (-) 3. Form the Frame Stretch the thread tightly around the four ends. Because the diagonals are equal and bisect each other, the resulting shape is a Rectangle. Every corner is exactly . C TEST DIFFERENT ANGLES Notice: No matter how you cross the sticks, the corners stay . Back DoneWriting the steps down Take the two sticks of equal length. Find the exact midpoint of each stick (you can use the thread to measure the length and fold it in half to find the center). Join the two sticks together at their midpoints to form an 'X' shape. Connect the four tips of the sticks with the thread. The shape formed by the thread is a Rectangle. Since every corner of a rectangle is 90° , the angle between adjacent threads at any corner will be exactly 90°