Question

an archaeologist is examining an image of a bone - fragment on her computer screen, which has a coordinate grid behind it. the bone fragment is shown below.
part a: the archaeologist turns the fragment over, reflecting it over the y - axis. what are the new coordinates of the vertices?

Explanation:

Step1: Recall reflection rule

When reflecting a point $(x,y)$ over the y - axis, the rule is $(x,y)\to(-x,y)$.

Step2: Apply rule to vertices

Assume the original vertices of the bone - fragment (in the coordinate grid) are $(x_1,y_1),(x_2,y_2),\cdots$. After reflection over the y - axis, the new vertices will be $(-x_1,y_1),(-x_2,y_2),\cdots$.

Answer:

The new coordinates of the vertices are obtained by changing the sign of the x - coordinates of the original vertices while keeping the y - coordinates the same. For example, if an original vertex is $(3, 2)$, the new vertex after reflection over the y - axis is $(-3,2)$. Without the actual original coordinates given in the image, we can only state the general rule.