please help me on 18
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You need to find the area of the square 1st
The formula is bxh
That means 16x16 (in your question)
= 256
Then you find the area of the circle which is
Pie x radius squared
To find the radius it’s half the diameter( which in your case is half the length)
So it’s 16 ~ 2 =8
= pie (3.14) x 64
= 200.96
To find shaded region
The area of rectangle - the area of circle
= 256-200.96
= 55.04
Then rounded = 50 (I think)