Answer:
17m
(Anyone can correct me if I'm wrong)
Step-by-step explanation:
The following equation would be used: [tex]A=\frac{a+b}{2} h[/tex]
We would simply substitute the given values, move the values around then we would get our answer:
[tex]230.945=18.7\frac{7.7+b}{2}\\\\230.945=9.35(7.7+b)\\\\b+7.7=24.7\\\\b=17m[/tex]
