Answer:
The base of the second parallelogram is 51cm.
Step-by-step explanation:
If the parallelograms are similar, it means by applying the same scale factor to all the sides in one gives you the other. The question tells us the height of the first shape is 8cm and the height of the second shape is 34cm. That means the scale factor is:
Apply this same scale factor to the base of the first shape to find the base of the second: