Y=2x+5
goes up by 2, which is the gradient and 5 is the y intercept
<span>What do you have to select? tell me what u have to select and i can help you</span>
Because if you multiply 2 different irrational numbers (like the following)

You will get an irrational answer.
BUT
if you multiply the same square root (which are both irrational, you get a rational number)
Answer:
The third one. The square in the top left can only fold to the right or down.... which means there is guaranteed to be an open side remaining on the square.