Ex.4.2 Q4 Linear Equations in Two Variables Solution - NCERT Maths Class 9

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Question

Find the value of \(k,\) if \(x = 2, y = 1\) is a solution of the equation \(2x + 3y = k.\)

 Video Solution
Linear Equations In Two Variables
Ex 4.2 | Question 4

Text Solution

What is known?

Linear equation \(\begin{align}2x + 3y = k.\end{align}\)

 What is Unknown?

Value of \(K\).

 Reasoning:

We can find value of \(k\) by substituting the values of \(x\) and \(y\) in the given equation. 

Steps:

Given :

\(2x + 3y = k\) is the Linear Equation ---------------- Equation (\(1\))

  • \(x = 2\)
  • \(y = 1\)
  • \(k =?\)

By substituting the values of \(x\) and \(y\) in Equation (\(1\)),

\[\begin{align}&2x + 3y = k\\&\Rightarrow(2)(2) + 3(1) = k\\&\Rightarrow4 + 3 = k\end{align}\]

Hence, \(k = 7\)

Therefore, the value of \(k\) is \(7.\)

  
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