Question

Find the value of k if x = 3, y = 1 is a solution of the equation 2x + 5y = k.

Answer 1

Given equation: $2x+5y=k$; $x=3,y=1$ are the solutions of the given equation.
So, they must satisfy the given equation.
Putting $x=3,y=1$ in the equation, we get:
$$\begin{gathered} \Rightarrow 2\times 3+5\times 1=k \\ \Rightarrow 6+5=k \end{gathered}$$
$\Rightarrow k=11$
Hence, the value of $k=11$.