Question

Which of these equations represents a straight line?

• A. $ax+by+c=0;$ where $a$ and $b$ are not both zero at the same time.
• B. $a{x}^2+b{y}^2+c=0;$ where $a$ and $b$ are both non-zero.
• C. $\frac{x^2}{a^2}+\frac{y^2}{b^2}=1;$ where $a$ and $b$ are both non-zero.
• D. $\frac{x^2}{a^2}-\frac{y^2}{b^2}=1;$ where $a$ and $b$ are both non-zero.

Answer 1

Answer: (A)

$ax+by+c=0;$ where $a$ and $b$ are not both zero at the same time.

Equation of straight line is of the form, $ax+by+c=0$.
Hence, the option $A$ is correct.
Note that its also necessary that $a$ and $b$ cannot both be zero at the same time.