Straight Line And Pair Of Straight Lines Ques 21
- The number of integer values of $m$, for which the $x$-coordinate of the point of intersection of the lines $3 x+4 y=9$ and $y=m x+1$ is also an integer, is (2001,1M)
2
0
4
1
Show Answer
Solution:
Formula:
- On solving equations $3 x+4 y=9$ and $y=m x+1$, we get
$$ x=\frac{5}{3+4 m} $$
Now, for $x$ to be an integer,
$$ 3+4 m= \pm 7 \text { or } \pm 1 $$
The integral values of $m$ satisfying these conditions are -2 and -1 .
BETA
