box1: y-axis
box2: dilation
box3:7
Explanation
[tex]\begin{gathered} Let\text{ } \\ (x,y)\text{ the initial image} \end{gathered}[/tex]
Step 1
[tex](x,y)\rightarrow(-x,y)[/tex]
we can see y coordinate is the same, but x coordiante has opposite sign(its sign is changed)
hence
When you reflect a point across the y-axis, the y-coordinate remains the same, but the x-coordinate is transformed into its opposite (its sign is changed),so for box 1 the answer is
y-axis
Step 2
[tex](x,y)\rightarrow(0.5x,0.5y)[/tex]
A dilation (similarity transformation) is a transformation that changes the size of a figure. It requires a center point and a scale factor , k
in this case k=0.5
[tex]\begin{gathered} (x,y)\rightarrow(kx,ky) \\ (x,y)\rightarrow(0.5x,0.5y) \\ so \\ k=0.5 \end{gathered}[/tex]
so, for box 2, the answer is dilation
Step 3
[tex](x,y)\rightarrow(x-7,y+7)[/tex]
when you traslate horizontally , you affect the x coordinates, so
[tex]\begin{gathered} x+k\rightarrow moves\text{ the xcoordiantes k espaces to the rigth} \\ x-k\rightarrow moves\text{ the xcoordiantes k espaces to the left} \end{gathered}[/tex]
hence, in this case
[tex](x-7)\rightarrow the\text{ figure is traslated 7 units to the left}[/tex]
and
when you traslate the figure vertically, you move on y axis, it means
[tex]\begin{gathered} y+k=\text{moves the shape up} \\ y-k=\text{moves the shape down} \end{gathered}[/tex]
hence, in this case
[tex]y+7\rightarrow th\text{e figure is traslated 7 units up}[/tex]
I hope this helps you