Question

The number of integer values of $m$, for which the $x$-coordinate of the point of intersection of the lines $3x + 4y = 9$ and $y = mx + 1$ is also an integer, is

• A. 0
• B. 2
• C. 4
• D. 1

Answer 1

Answer: (B)

2

Answer 2

Given lines are, $3 x+4 y=9$ ...(i)
$y=m x+1$ ...(ii)
Solving Eqs. (i) and (ii), we get
$x=\frac{5}{3+4 m}$
If $m=-1$, then $x=-5$ and $m=-2$, then $x=-1$ are the only possibilities.