Question

Triangle ABC with vertices A(–4, –4), B(–1, –2), C(3, –1) is rotated 180° about the origin. What are the coordinates of triangle A′B′C′?

Answer 1

A(4, 4), B(1, 2), C(-3, 1)

Explanation:

Because the triangle is rotated 180° about the origin you are just rotating it 2 quadrants, the size stays the same.

The rule for rotating 180° is if (x, y) is rotating 180° then the new position is (-x, -y).

So:

A(-4, -4), which then becomes B(-(-4), -(-4) ) = B(4, 4)

B(–1, –2) which becomes B(-(–1), –(-2) ) = B(1, 2)

C(3, –1) which becomes C(-3, –(-1) ) = C(-3, 1)