Which of the following are the correct coordinates when the point (1,8) is rotated 180 degrees anticlockwise about the origin

Answer 1

(-1,-8) is the point symmetrical about the origin from (1,8)

just change the signs of both the x and y cooridniates.

It might help to plot the points on a graph

which is the same as rotating it about the origin 180 degrees, either anticlockwise or clockwise

find the equation through the origin and the given point. It's y=8x

(1,8) is a distance = sqr(1^2 +8^2) = sqr65 from the origin, in quadrant I

(-1,-8) is the same distance from the origin, on the same line, but in quadrant III

the equation f(x) = 8x is an "odd" function. f(x) =-f(-x) -y=8(-x)