A thin piece of 40 m wire is cut in two. One piece is a circle with radius of r. Other is a square. No wire is left over. Which represents total area of circle and square in terms of r?
a. Î r2
b. Î r2 + 10
c. Πr2 + ¼ π2r2
d. Î r2 + (40 - 2Ï€r)2
e. Πr2 + (10 - ½ Πr)2
40m wire
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Circumference of a circle= 2*pi*r
Perimeter of a square=4*s. S represents the length of each side of the square.
2*pi*r+ 4s= 40
Total area of the circle and square= pi*r^2+s^2
Express s in terms of r.
40-2*pi*r/4=10-(pi*r)/(2)
Total area of the circle and square in terms of r:
pi*r^2+(10-(pi*r)/(2))^(2)
E should be your answer.
Perimeter of a square=4*s. S represents the length of each side of the square.
2*pi*r+ 4s= 40
Total area of the circle and square= pi*r^2+s^2
Express s in terms of r.
40-2*pi*r/4=10-(pi*r)/(2)
Total area of the circle and square in terms of r:
pi*r^2+(10-(pi*r)/(2))^(2)
E should be your answer.