Answer:
3x - y = 0; 2x - y = -5
Step-by-step explanation:
Let x be the present age of Hans and y be the present age of Grace,
Since, in present Grace is three times as old as Hans,
⇒ y = 3x
⇒ 3x - y = 0
Now, after 5 years,
The age of Hans = x + 5,
And, the age of Grace = y + 5
Also, in 5 years Grace will be twice as old as Hans is then,
⇒ y + 5 = 2 ( x + 5 )
⇒ y + 5 = 2x + 10
⇒ 2x - y = -5
Hence, the required system of linear equations is,
3x - y = 0; 2x - y = -5
Since 2 croissants = $3 we can work out that 1 croissant = $1.50
Multiply $1.50 by 31 and we get $46.50
Therefore 31 croissants is $46.50
Well let's see.

The equation has exactly one solution.
Hope this helps.
Answer:
The answer is True. Just trust me on this one.