Question

From a square cardboard ,a circle of biggest area was cut off. If the area of the circle was 154 cm .calculat the original area of the cardboard.[π=22/7]

Answer 1

the radius of the largest circle must be
side of the square/2=a/2
area of circle=$\pi (\frac{a}{2})^{2}=\pi \frac{ a^{2} }{4}=154$
$\pi a^{2}=616$
$a= \sqrt{ \frac{616*7}{22}}=14 cm$
Area of square =$a^{2}=196 cm^{2}$

Answer 2

the radius of the largest circle must be 
side of the square/2=a/2
area of circle=


Area of square =