Question

Triangle A B C has vertices (1,4),(5,6) and (3,10) It is reflected across the y axis forming triangle A’B’C’. What are the vertices of the new triangle?

Answer 1

Given:

The coordinates of triangle ∆ABC are (1,4), (5,6) and (3,10).

The triangle is reflected across y axis forming ∆A'B'C'.

The objective is to find the vertices of the new triangle.

Explanation:

If a triangle with coordinate (a,b) is reflected across y axis, then the change in reflected coordinate will be (-a,b).

If a triangle with coordinate (a,b) is reflected across x axis, then the change in reflected coordinate will be (a,-b).

To find vertices:

Since, the given triangle is reflected across y axis, then the vertices of new triangle will be,

$\begin{gathered} A^{\prime}=(-1,4) \\ B^{\prime}=(-5,6) \\ C^{\prime}=(-3,10) \end{gathered}$

Hence, the vertices of the new triangle are (-1,4), (-5,6) and (-3,10).