Gujarat BoardEnglish MediumSTD 9MathsLines and Angles4 Marks
Question
Prove that through a given point, we can draw only one perpendicular to a given line. [Hint: Use proof by contradiction].
✓
Answer
From the point $P$, a perpendicular $PM$ is drawn to the given line $AB$. $\therefore\ \angle\text{PMB}=90^\circ$ Let if possible, we can draw another perpendicular $PN$ to the line $AB$. then, $\angle\text{PMB}=90^\circ$ $\angle\text{PMB}=\angle\text{PNB},$ which is possible only when $PM$ and $PN$ coincide with each other.
Hence, through a given point, we can draw only one perpendicular to a given line.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.