# Quadratic Equations and Simultaneous Equations MCQs - Math Test 9

MCQ. Value of b^{2} - 4ac determines nature of roots, for not-real roots, b^{2} - 4ac is:

- lesser than 0.
- equal to 0.
- greater than 0.
- None of above.

A

MCQ. Sum of roots of a quadratic equation is equal to:

- -b ⁄ 2a.
- -2b ⁄ a.
- -b ⁄ a.
- b ⁄ a.

C

MCQ. Length of line joining two points (x1, y1) and (x2, y2) is:

- (x2 - x1) + (y2 - y1).
- ?((x2 - x1) + (y2 - y1)).
- ?((x2 - x1)
^{2}+ (y2 - y1)^{2}). - (y2 - y1) ⁄ (x2 - x1).

C

MCQ. Coordinates of midpoint of line joining two points (x1, y1) and (x2, y2) are:

- ((x2 - x1) ⁄ 2, (y2 - y1) ⁄ 2).
- ((x2 + x1) ⁄ 2, (y2 + y1) ⁄ 2).
- ((x2 - x1), (y2 - y1)).
- ((x2 + x1), (y2 + y1)).

B

MCQ. Coordinates of midpoint of line joining two points (1, 2) and (4, 8) are:

- (2.5, 10).
- (5, 5).
- (5, 10).
- (2.5, 5).

D