## Detailed description

Cartesian plane shown with right-angled triangles T, $$T^\prime$$, $$T^{\prime\prime}$$ and $$T^{\prime\prime\prime}$$. Labelled ABC, $$A^\prime B^\prime C^\prime$$, $$A^{\prime\prime} B^{\prime\prime} C^{\prime\prime}$$ and $$A^{\prime\prime\prime} B^{\prime\prime\prime} C^{\prime\prime\prime}$$ . Triangle is formed from triangle T by rotating T about C by 120° in a clockwise direction.

Coordinates:

A(1, 8); B(1, 5); C( 2, 5)

$$A^{\prime\prime}$$(–1, 8); $$B^{\prime\prime}$$(–1, 5); $$C^{\prime\prime}$$(–2, 5)

$$A^{\prime\prime\prime}$$(5, 4); $$B^{\prime\prime\prime}$$(5, 1); $$C^{\prime\prime\prime}$$(6, 1)