In the figure, ABCD is a parallelogram and ABE is the triangle which stands on the base AB

For the triangle ABE, a = 30 cm, b = 28 cm, c = 26 cm.
∴ s = a +b + c/ 2 = 30 +28+ 26 /2 cm = 42 cm


Now, area of the parallelogram = base × height
⇒ 336 = 28 × height
[Given, area of the triangle = area of the parallelogram]
⇒ Height of the parallelogram = 336/ 28 cm = 12 cm Ans.