Question

Which of the following is not a linear equation in one variable? (Consider a, b and c as constants and x as variable)

• A. $a^{3}x+b^2=c^4$
• B. $ax+b=c$
• C. $abx+c=0$
• D. $a{x}^4+b{x}^2+c=0$

Answer 1

The correct option is D

$a{x}^4+b{x}^2+c=0$

The general form of a linear equation in one variable is: $ax+b=c$ where a and b are constants and x is a variable.

So, in a linear equation the degree is 1 i.e., highest power in the variable is 1.
But in $a{x}^4+b{x}^2+c=0$ highest power for x is 4. Hence, it is not linear.