Quantitative Aptitude - Arithmetic Ability Questions

In the following question, select the odd letter/letters from the given alternatives.

The number of solutions of the pair of linear equations x + 2y - 8 = 0 and 2x + 4y = 16 is

If 5x - ­5(3x ­- 2) < 4x -­ 1 < 2 + 2x, then x can take which of the following values?

If a + b = 10 and ab- 13 = -ba - 11, then what is the value of 3ab + 4a2 + 5b2 ?

If 9x - 6(3 - x) = 12, then the value of x is

The vertical angle A of an isosceles triangle ΔABC is three times the angle B of it. The measure of the angle A is

For what value of 'y', x2 + 112x + y2 is a perfect square?

If x stands for addition, / stands for subtraction, + stands for multiplication and - stands for division, then what is the value of 20 x 8 / 8 - 4 + 2 ?