Q90 / 180 · KCET 2019 · Mathematics
A line cuts off equal intercepts on the co-ordinate axes. The angle made by this line with the
positive direction of \( X \)-axis is
positive direction of \( X \)-axis is
- A\( 90^{\circ} \)
- Correct answerB\( 135^{\circ} \)
- C\( 45^{\circ} \)
- D\( 120^{\circ} \)
Solution
(B)
\[ \begin{array}{l} x+y=a \\ \frac{d y}{d x}=-1 \\ \tan \theta=-1 \\ \theta=\pi-\frac{\Pi}{4}=\frac{3 \Pi}{4} \Rightarrow \theta=135^{\circ} \end{array} \]
\[ \begin{array}{l} x+y=a \\ \frac{d y}{d x}=-1 \\ \tan \theta=-1 \\ \theta=\pi-\frac{\Pi}{4}=\frac{3 \Pi}{4} \Rightarrow \theta=135^{\circ} \end{array} \]
Hence, the correct answer is option: 'B'.