Answer:
12 centimeters
Explanation:
The side lengths of the triangle are: 26, 28, and 30 centimeters
a = 26 cm, b = 28 cm, c = 30 cm
To find the area, we first must find the semi-perimeter with the following equation:
s = (a+b+c)/2
= (28+26+30)/2
= 42 centimeters
Now, to find the area, we can use Heron's formula:
A =



336 squared centimeters
Since the area of the parallelogram is equal to the area of our triangle:
Area of Parallelogram = Area of Triangle
base ⋅ height = 336 squared centimeters
28 ⋅ height = 336 squared centimeters
height = 336/28
height = 12 centimeters