Question

The rule ry-axis • RO, 90°(x, y) is applied to ΔABC.

Answer 1

Consider triangle ABC with vertices at points A(2,-4), B(4,-4) and C(4,-2).

1. The rotation $R_{O, 90^{\circ}}(x, y)$ acts with the rule:

$(x,y)\rightarrow (-y,x).$

Then:

• $A(2,-4)\rightarrow A'(4,2);$
• $B(4,-4)\rightarrow B'(4,4);$
• $C(4,-2)\rightarrow C'(2,4).$

2. The reflection across the y-axis has a rule:

$(x,y)\rightarrow (-x,y).$

So,

• $A'(4,2)\rightarrow A''(-4,2);$
• $B'(4,4)\rightarrow B''(-4,4);$
• $C'(2,4)\rightarrow C''(-2,4).$

Triangle A''B''C'' is exactly the same as tiangle from figure 1.

Answer: correct choice is 1.

Answer 2

The answer is number 1