The solution of the equation ax + b = 0 is
Question:

The solution of the equation ax + b = 0 is

(a) $x=\frac{a}{b}$

(b) $x=-b$

(c) $x=\frac{-b}{a}$

(d) $x=\frac{b}{a}$

Solution:

(c) Given equation is $a x+b=0$

$\Rightarrow$ $a x=-b \quad$ [transposing $b$ to RHS]

$\Rightarrow$ $\frac{a x}{a}=\frac{-b}{a}$ [dividing both sides by a]

$\therefore$ $x=\frac{-b}{a}$

Hence, the solution of the equation $a x+b=0$ is $x=-\frac{b}{a}$.