Answer:
Step-by-step explanation:
a = 5 ft, b = 8 ft, c = 9 ft
semiperimeter s = (a+b+c)/2
= (5 + 8 + 9)/2
= 11 ft
area = √(s(s-a)(s-b)(s-c))
= √[11(11-5)(11-8)(11-9)]
= √396 ft²
area = ½(9)h = √396
4.5h = √396
h = √396/4.5 ≅ 4.42 ft
