Question

Find the coordinates of the points on the y-axis, which are at a distance of 10 units from the point (-8, 4).

Answer 1

Let the coordinates of the point on y-axis be (0, y).
From the given information, we have:
`sqrt((0 + 8)^2 + (y - 4)^2)` = 10
(0 + 8)² + (y - 4)² = 100
64 + y² + 16 - 8y = 100
y² - 8y - 20 = 0
y² - 10y + 2y - 20 = 0
y(y - 10) + 2(y - 10) = 0
(y - 10)(y + 2) = 0
y = 10, - 2
Thus, the required co-ordinates of the points on y-axis are (0, 10) and (0, -2).