Fill in the blanks:

(a) The y-coordinate of a point on the x-axis is _________.

b) The x-coordinate is called as _________.

(c) The x-axis and Y-axis intersect at _________.

(d) If a point (x,y) ≠ (0,0) is in the third quadrant, then x + y has _________sign.

(e) If a point (x,y) lies above horizontal axis, then y is always _________.

(f) The point of intersection of x = y and x = −y is _________.

(g) The line y =4x +5 intersects y-axis at the point _________.

(a) The y-coordinate of a point on the x-axis is zero.

Explanation:

On x – axis, the values of x keep on increasing and value of y remains zero as there is no movement in vertical direction.

(b) The x-coordinate is called as abscissa.

Explanation: The x coordinate of a coordinate system is called abscissa and y coordinate is called ordinate.

(c) The x-axis and Y-axis intersect at origin (0,0).

At origin values of x and y coordinates are 0 and thus they start increasing or decreasing in value from origin. Thus, they intersect at origin.

(d) If a point (x,y) ≠ (0,0) is in the third quadrant, then x + y has –(negative) sign.

Explanation: In the third quadrant, x and y both are negative, thus x – y = -x + (-y) = - (x + y)

And so its negative.

(e) If a point (x,y) lies above horizontal axis, then y is always +(positive).

(As, in first and second quadrant y is positive.)

(f) The point of intersection of x = y and x = −y is origin(0,0).

(As, after solving both the equations simultaneously by using substitution method, we get- x=0 and y=0).

(g) The line y =4x +5 intersects y-axis at the point (0, 5).

(Since, the point is at y-axis implies that x=0, and after substituting x=0 in equation, we get y=5.