Question
The range of values of the ordinate of a point moving on the line $$x=1,$$ and always remaining in the interior of the triangle formed by the lines $$y=x$$ the $$x$$-axis and $$x+y=4,$$ is :
A.
$$\left( {0,\,1} \right)$$
B.
$$\left[ {0,\,1} \right]$$
C.
$$\left[ {0,\,4} \right]$$
D.
none of these
Answer :
$$\left( {0,\,1} \right)$$
Solution :

From the figure, $$y$$-coordinates of $$P$$ vary from $$0$$ to $$1$$. So, to be an interior point,
$$0<$$ ordinate of $$P<1$$