Answer:
1
Step-by-step explanation:
Given triangle ABC with vertices at points A(2,-4), B(4,-4) and C(4,-2).
1. Rotate this triangle anticlockwise by 90° angle over the origin. This rotation has the rule
[tex](x,y)\rightarrow (-y,x),[/tex]
then
[tex]A(2,-4)\rightarrow A'(4,2)\\ \\B(4,-4)\rightarrow B'(4,4)\\ \\C(4,-2)\rightarrow C'(2,4)[/tex]
2. Reflect triangle A'B'C' across the y-axis. This reflection has the rule
[tex](x,y)\rightarrow (-x,y),[/tex]
then
[tex]A'(4,2)\rightarrow A''(-4,2)\\ \\B'(4,4)\rightarrow B''(-4,4)\\ \\C'(2,4)\rightarrow C''(-2,4)[/tex]
These are vertices of triangle 1
