Question

Triangle ABC has vertices at A(x,y), B(-r,s), and C(-p,-q). The triangle is then reflected across the y-axis to create triangle A'B'C'. Find the coordinates of A', B', and C'.

Answer 1

To find the coordinates of a point reflected across the y-axis, we apply this rule:
(x, y) => (-x, y).

This rule simply involves changing the sign of the x-coordinate, while the y-coordinate remains the same.

So, given points A(x,y), B(-r,s), and C(-p,-q), we will apply the above rule.

The coordinates of A(x,y) reflect to become A'(-x,y).

The coordinates of B(-r,s) reflect to become B'(r,s).

And the coordinates of C(-p,-q) reflect to become C'(p,-q).

So, the reflected vertices of our triangle ABC to become A'B'C' are A'(-x,y), B'(r,s), and C'(p,-q).