Answer:
The radius is 3 cm
Step-by-step explanation:
[tex]45 \pi =\pi \: r^{2} \times 5[/tex]
[tex]45 \times \frac{22}{7} = \frac{22}{7} \times r^{2} \times 5[/tex]
[tex] \frac{990}{7} =\frac{110}{5} \times r^{2} [/tex]
[tex]141.43 = 22 \times {r}^{2} [/tex]
[tex]22 {r}^{2} = 141.43[/tex]
[tex] {r}^{2} = 6.43[/tex]
[tex]r = \sqrt{6.43} [/tex]
[tex]r = 2.54[/tex]
[tex]r = 3[/tex]
