Question

give me a perfect answer

Answer 1

$area \: of \: trap. = \frac{1}{2} \times (10 + 4) \times r = 24.5 {cm}^{2}$
$\\ \\ area(24.5) \: = 7r \\ \\ r = 3.5cm$
$area \: of \: sector \: = \frac{\pi \: {r}^{2} \times 90 }{360} \\ \\ = > \frac{22}{7} \times 3.5 \times 3.5 \times 90 \times \frac{1}{360} = \frac{38.5}{4}$
$24.5 - 9.6 = 14.9 \: {cm}^{2}$