Question

Solve the equation $3x-9=0$ by the trial and error method

Answer 1

Solving the equation

A statement of equality which involves one or more variables is called an equation.

Given equation is $3x-9=0$

RHS of the equation is zero .In LHS, a whole number $9$ is subtracted from a multiple of $3$$3$.Thus we need to guess several values of $x$ to find the values of LHS that becomes equal to RHS as shown in the table below.

$\mathit{x}$	LHS$\mathbf{=}\mathbf{3}\mathit{x}\mathbf{-}\mathbf{9}$	RHS$\mathbf{=}\mathbf{0}$
$1$	$3\times 1-9=-6$	$0$
$2$	$3\times 2-9=-3$	$0$
$3$	$3\times 3-9=0$	$0$

For $x=3$,LHS=RHS.

Hence the solution of the equation $3x-9=0$ is $x=3$