The figure shows a square with sides 14 cm. Calculate the area and perimeter of the shaded region. (Take π=22/7)
Jawaban:
AREA = 98cm²
PERIMETER = 88cm
Penjelasan dengan langkah-langkah:
Info :
s ( side ) = 14cm
r ( radius ) will be half of s (side)
r ( radius ) = 7cm
π = 22/7
______________
Area :
=> we will divide a square into 2 rectangles :
A rec = s × r
A rec = 14cm × 7cm
A rec = 98cm²
=> Area of Semicircle :
A sc = ½ × π × r²
A sc = ½ × 22/7 × (7cm²)
A sc = 11 × 7cm²
A sc = 77cm²
=> Area equal to 1 Area of semicircle +
(1 Area of rectangle – 1 Area of semicircle)
A = A sc + (A rec – A sc)
A = 77cm² + ( 98cm² – 77cm² )
A = 77cm² + 21cm²
A = 98cm²
Perimeter :
=> Perimeter ( P ) in the question formed by
4 perimeter of ¼ circle :
P = P ¼ circle + P ¼ circle + P ¼ circle + P ¼ circle
P = P circle
P = 2 × π × s
P = 2 × 22/7 × 14cm
P = 88cm