Quantitative Aptitude - Arithmetic Ability Questions

One of four words is a class to which the other three belong. Identify the class.

What is the equation of the line passing through the point (2,-3) and making an angle of -45°with the positive X-axis?

What is the reflection of the point (2, 3) in the line y = 4?

Product of digits of a 2-digit number is 72. If we add 9 to the number, the new number obtained is a number formed by interchange of the digits. Find the number.

Find  two  natural  numbers  whose  sum  is  85 andtheleast common multiple is 102.

The area of a square is equal to its side, if the side is 1 unit.

If sec2A cosec2A = x, then x is

Select the odd word/letters/number/number pair from the given alternatives.