The graph of the pair of equations $x+y=7$ and $3x+3y=21$ is:

Pathik travels $600 \, km$ to his home partly by train and partly by car. He takes $8$ hours if he travels $120 \, km$ by train and the rest by car. He takes $20$ minutes longer if he travels $200 \, km$ by train and the rest by car. Find the speed of the train and the car.

The solution set of a pair of equations $x+y-1=0$ and $2x+2y-2=0$ is $\ldots \ldots \ldots \ldots$

Examine graphically whether the pair of equations $2x + 4y = 9$ and $3x + 6y = \frac{27}{2}$ is consistent.

Which of the following groups matches the data of Part $I$ with the data of Part $II$?

Part $I$	Part $II$
$1. x+2y=3, 2x+4y=5$	$a. \text{Solution set is a singleton set.}$
$2. 2x+3y=6, x+\frac{3}{2}y=3$	$b. \text{Solution set is an empty set.}$
$3. 3x-y=0, x-y+6=0$	$c. \text{Solution set is an infinite set.}$
	$d. \text{Solution set contains two members.}$

In a two-digit number,the digit at the unit's place is $(x+1)$ and the digit at the ten's place is $(x+2)$,then that number is $\ldots \ldots \ldots \ldots .$