Respuesta :
Answer:
Step-by-step explanation:
Area of circle = 78.5 in²
πr² = 78.5
3.14*r² = 78.5
[tex]r^{2}=\frac{78.5}{3.14}\\\\=\frac{78.5*100}{3.14*100}\\\\=\frac{7850}{314}\\\\r^{2}=25\\r=\sqrt{25}=\sqrt{5*5}\\\\[/tex]
r = 5 in
Answer:
[tex]area = \pi \times r ^{2} \\ 78.5 = 3.14 {r}^{2} \\ \frac{78.5}{3.14} = \frac{3.14 {r}^{2} }{3.14} \\ {r}^{2} = 25 \\ r = \sqrt{25} \\ r = 5inches[/tex]