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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? - Mathematics

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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:

  1. How much wire is left?
  2. If this left out wire is used for making an equilateral triangle. What is the length of each side of the triangle so formed?
योग
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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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अध्याय 10: Algebraic Expressions - Exercise [पृष्ठ ३२५]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 7
अध्याय 10 Algebraic Expressions
Exercise | Q 83. | पृष्ठ ३२५

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