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प्रश्न
A wire is (7x – 3) metres long. A length of (3x – 4) metres is cut for use. Now, answer the following questions:
- How much wire is left?
- If this left out wire is used for making an equilateral triangle. What is the length of each side of the triangle so formed?
उत्तर
Given, length of wire = (7x – 3)m
and wire cut for use has length = (3x – 4)m
a. Left wire = (7x – 3) – (3x – 4)
= 7x – 3 – 3x + 4
= 7x – 3x – 3 + 4
= (4x + 1)m
b. ∴ Left wire = (4x + 1)m
∴ Perimeter of equilateral triangle = Length of wire left
⇒ 3 × (side) = 4x + 1
⇒ Side = `(4x +1)/3 = 1/3 (4x + 1)m`.
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| S. No |
Expression |
Terms | |||||||||
| 1st | 2nd | 3rd | 4th | 5th | ... | 10th | ... | 100th | ... | ||
| 1 | 2n - 1 | 1 | 3 | 5 | 7 | 9 | - | 19 | - | - | - |
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| 3 | 4n + 1 | 5 | 9 | 13 | 17 | - | - | - | - | - | - |
| 4 | 7n + 20 | 27 | 34 | 41 | 48 | - | - | - | - | - | - |
| 5 | n2 + 1 | 2 | 5 | 10 | 17 | - | - | - | - | 10001 | - |
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