<h2><em><u>Answer : </u></em>The area of triangle is 864 cm² and the height corresponding to the longest side is 28.8 cm.</h2><h2 />
Answer:

Step-by-step explanation:
We can notice that the the prism provided is a rectangular prism.
By definition, The lateral area of a rectangular prism can be calculated by multiplying the perimeter of its base by its height.
The height is:

Then, the perimeter of the base is:

Then the lateral area is:

13 + 21 = 13- -21
The minus sign and negative cancel each other out.
12 is the answer your looking for
109 is your answer nchfiknvbi