The quadratic equation has two solutions. Either x = -3 or x = 4.
In the first case, x -3 = -6.
In the second case x -3 = 1. Hence, this is a D answer because one case is less than 0, and one is more.

Make a sketch. You should be able to see that the distance to the origin in both cases will be the same. (The segments joining the points to the origin are both hypotenuses of right triangles with sides 3 and 7.)

At nine o'clock the hour hand points exactly to 9 and the minute hand exactly to 12, making a 90 degree angle.
At nine thirty, the minute hand points exactly to 6, and the hour hand points to half way between nine and ten, giving more than 90 degrees (90 + 15)

A score of three could be obtained from 1 + 2 or 2 +1. But to get a score of 2 you need to have 1 + 1 only which makes 2 a less probable score.

The area of the triangle is ½ base x height = 9
The rectangle could be drawn with a length of nearly five and a breadth of less than one which would give a very small area. But what is teh maximum arae possible? This will always be the area whan you make the rectangle into a square. In this case the side of the square will be 2.5 and the area will be 6.25, which is less than 9.

Since l,m, and n are parallel, x must be equal to the angle between AB and line m (corresponding angles). And y must be equal to the angle between BC and line m. So the angle at B = x + y = 90

There is no need to calculate here. But neither should you fall into the trap. The average speed is not 45. Since Pedro spends more time on the leg of the trip when he is traveling at 40km/hour, than when he travels at 50, the average speed will be closer to 40 than it is to 50. This means the average value must be less than 45. (If you want to confirm this then you can use the formula [average speed = total distance / total time], but you will have to pick a value for the distance (say 20 km) and then work out the time for each leg)

Since 50 per cent of the students study French that gives 16 students who study French. The number of boys in the class is 25 percent of 32 = 8. Now if all the boys study French that will leave 8 girls who study French, and this will be the minimum number of girls taking this subject. (If fewer boys take it, the number of girls will go up). Hence the number of girls taking French cannot be less than 8, making the left column larger.

The value of x must be more than the value of y, because x is an external angle of the triangle, and is therefore equal to the sum of the two opposite interior angles of which y is only one.

More than twice is not specific enough; it could mean three, four or even more times what Sita and Tim have. Hence, the number that Ravi has could be less or more than three times Sita and Tim's total. Hence, this is a D answer.