Let the point on the line \( 3x + 5y = 15 \) be \( (a, b) \).
Since the point is equidistant from the coordinate axes, we have \( |a| = |b| \), which means \( b = a \) or \( b = -a \).
Case 1: \( b = a \)
Substitute \( y = x \) into the equation of the line:
\( 3x + 5x = 15 \)
\( 8x = 15 \)
\( x = \frac{15}{8} \)
So, \( a = \frac{15}{8} \) and \( b = \frac{15}{8} \).
The point is \( (\frac{15}{8}, \frac{15}{8}) \), which lies in the \( 1^{st} \) quadrant.
Case 2: \( b = -a \)
Substitute \( y = -x \) into the equation of the line:
\( 3x + 5(-x) = 15 \)
\( 3x - 5x = 15 \)
\( -2x = 15 \)
\( x = -\frac{15}{2} \)
So, \( a = -\frac{15}{2} \) and \( b = -(-\frac{15}{2}) = \frac{15}{2} \).
The point is \( (-\frac{15}{2}, \frac{15}{2}) \), which lies in the \( 2^{nd} \) quadrant.
Therefore, the point lies in either the \( 1^{st} \) quadrant or the \( 2^{nd} \) quadrant.