Area = (b * h)/2, b = 21 bu we don't know h, s we have to calculate it
To calculate the height "h" we can use pythagoras with a triangle rectangle with base = 21/2 = 10.5 and hypothenuse = 28, so the height "h" is:
28² = h² + 10.5² ==> h² = 28² - 10.5² = 784 - 110.25 = 673.75
h² = 673.75
h = 25.96
Now that we have the height, the Area of the triangle = (b * h)/2 = (21 * 25.96)/2 = 272.5
Answer:
272.5
