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Squares aur Rectangles Banana

Class 6 Maths · Chapter 8: Constructions se Khel · NCERT Ganita Prakash section 8.3

Seekho

Farhan rectangle ABCD banana chahta hai jisme AB = 6 cm aur BC = 4 cm. Pehle ek kachcha sketch planning mein madad karta hai: pehle kaunsi bhuja, aur har kona kahan.

Step 1: ruler se AB = 6 cm banao. Step 2: A aur B par 90° ki lines banao (protractor ya set square se). Step 3: har line par compass se 4 cm lagao: D aur C mil gaye. Step 4: D aur C jodo. Jaancho: DC bhi 6 cm hona chahiye.

Step 3 mein compass kyun? Kyunki compass theek wahi lambai baar-baar utaarta hai, har baar naape bina. Isliye constructions mein ye use hota hai.

5 cm bhuja wale square ke liye steps wahi hain, par har bhuja 5 cm. 18 cm perimeter aur 5 cm lambai wale rectangle ke liye pehle chaudai nikaalo: 18 ÷ 2 = 9, aur 9 − 5 = 4 cm.

18 ÷ 2 − 5 = 4

Explore: grid par har shape banao.

  1. 6 cm × 4 cm ka rectangle banao.
  2. 5 cm bhuja ka square banao.
  3. 18 cm perimeter aur 5 cm lambai ka rectangle banao.

Yaad rakho

  • Kachcha sketch construction plan karne mein madad karta hai.
  • Rectangle banane ke liye: ek bhuja, dono siron par right angle, compass se doosri bhuja lagao, jodo.

Quick check

Divit ne AB = 7 cm aur A aur B par 90° lines banaayi. Ab kya kare?

  1. Dono lines par compass se chaudai lagaaye
  2. A ke chaaron or gola banaaye
  3. A aur B phir se jode
  4. Pehle diagonal banaaye
Answer

Dono lines par compass se chaudai lagaaye. Ab har 90° line par chaudai par D aur C aate hain.

Socho

Agar sirf pata ho ki perimeter 20 cm hai, kya rectangle bana sakte ho? Kyun ya kyun nahi?

Ek answer

Ek bana sakte ho, par koi khaas wala nahi: 9 × 1, 8 × 2, 7 × 3, 6 × 4 aur 5 × 5 sabka perimeter 20 cm hai. Ek aur jaankaari chahiye, jaise lambai.

Practice

Teen levels (easy, medium, hard) ke naye sawaalon se practice karo, kuch hands-on, hints aur hal ke saath. Topic poora karne ke liye pichhle 5 mein se 4 sahi karo.