Q.Find the equation of the line which makes an intercept of $4$ on the x-axis and an intercept of $3$ on the y-axis.

Given both intercepts, use the intercept form $\dfrac{x}{a} + \dfrac{y}{b} = 1$.

When the x-intercept $a$ and y-intercept $b$ are both given, the intercept form applies directly:

Here $a = 4$ and $b = 3$, so

Multiply through by the LCM $12$ to clear denominators:

$3x + 4y = 12 \ \Rightarrow\ 3x + 4y - 12 = 0$ …

Placing the intercepts under the wrong variables — the x-intercept always sits under $x$ and the y-intercept under $y$. Also, when clearing denominators, every term (includi …