Question

Pre-Image PointsA (-5,-1)B (-4,2)C (0,-1)Coordinate Rule(x,y) → (x, 3y)

Answer 1

First, I will just rewrite the points

$\begin{gathered} A=(-5,-1) \\ \\ B=(-4,2) \\ \\ C=(0,-1) \end{gathered}$

The coordinate rule is

$(x,y)\rightarrow(x,3y)$

which means we will take all the y-coordinate of the points and multiply by 3, then

$\begin{gathered} A^{\prime}=(-5,3\cdot(-1)) \\ \\ B^{\prime}=(-4,3\cdot2) \\ \\ C^{\prime}=(0,3\cdot(-1)) \end{gathered}$

The result will be

$\begin{gathered} A^{\prime}=(-5,-3) \\ \\ B^{\prime}=(-4,6) \\ \\ C^{\prime}=(0,-3) \end{gathered}$

If we plot those points we can see the figure:

In orange, we have the pre-image figure and in blue the image.