Question

Coordinate of point P on a number line is -3 find the coordinates of points on the number line which are at a distance of 7 units from point P.​

Answer 1

Let point Q be at a distance of 8 units from P and on left side of P

Let point R be at a distance of 8 units from P and on right side of P.

i. Let the co-ordinate of point Q be x.

Co-ordinate of point P is -7.

Since, point Q is to the left of point P.

∴ -7 > x

∴ d(P, Q) = -7 - x

∴ 8 = -7 – x

∴ x = – 7 – 8

∴ x = -15

ii. Let the co-ordinate of point R be y. Co-ordinate of point P is -7. Since, point R is to the right of point P. ∴ y > -7 ∴ d(P, R) = 7- (-7) ∴ 8 = y + 7 ∴ 8 – 7 = 7 ∴ y = 1 ∴ The co-ordinates of the points at a distance of 8 units from P are -15 and