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Question
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?
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Solution
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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