Hey there!
When we find the volume of a prism, we compute the equation:
V = lwh
This means that volume is equal to length times width times height.
Therefore, it looks as if we need three measurements, when we only have two, the length and height. However, by looking at this picture, we see that the width is actually the same as the length as it is a square, therefore our dimensions are:
V = 7 * 7 * 3
V = 49 * 3
V = 147 units cubed
Hope this helps!
Answer is as shown in the picture.
Since each point of the triangle is going to be 1.5 times as far from the center of dilation, each side will increase by a factor of 1.5..
3 x 1.5 = 4.5m
4 x 1.5 = 6m
5 x 1.5 = 7.5m
So the perimeter of the new triangle will be 4.5 + 6 + 7.5 = 18 meters