Viva Voce: Find the Values of Abscissae | Lab Manuals for Class 9 PDF Download

Q.1. Is it correct that if any point on the X-axis, then the y-coordinate will be zero?

Yes, because the distance from X-axis is zero.

Q.2. In cartesian plane, the angle between two axes is not always!-90°.

False, the angle between two axes is always 90°.

Q.3. Is the point (-7,2), same as point (2,-7)?

No, in coordinates of a point, their order matters, so (-7,2) is not same as (2, – 7).

Q.4. A point (- 2,- 6) lies in which quadrant?

Third quadrant

Q.5. What is the image of (- 1, 4) in 3rd quadrant?

(-1,-4)

Q.6. What type of graph do you get for y = – 2?

A straight line parallel to X-axis at a distance of 2 units from origin below the X-axis.

Q.7. What do you mean by a cartesian system?

The system used to describe the position of a point in a plane, is called cartesian system.

Q.8. What is the condition that linear equation ax + by = c, c ≠ 0 perpendicular to any one of the axis?

The linear equation ax + by = c is perpendicular to any one of the axis, if either a = 0 or b = 0.

Q.9. Find the new coordinates of a point (2, 3), when we rotate the axes at 180° in anti-clockwise direction.

When we rotate the axes, the positive X and Y-axes will become negative. So, the new coordinates will be (-2, -3).

Q.10. In cartesian system, X-axis and Y-axis divide the graph paper in how many quadrants?

Four quadrants

Q.11. What type of graph do you get forx = – 2?

A straight line parallel to Y-axis at a distance of 2 units from origin lying in the left side of Y-axis.

Q.12. What is the image of (- 3, -1) in 2nd quadrant?

(-3,1)

Q.13. What is the ordinate of point lying in third quadrant at a distance of 2 units from X-axis and 5 units from Y-axis?

– 2, because is third quadrant y-coordinate is negative.