Answer:
Gọi AH là đường cao kẻ từ A đến BC
Xét tam giác AHC vuông tại H
Suy ra AH = HC. cotA= 9.cot35° = 12,9
Xét tam giác AHB vuông tại H
Suy ra BH = AH.tanA = 12,9.tan61°=23,37
Ta có BC= HC+ HB= 9+23,27 =32,27
Diện tích tam giác ABC = 1/2 × AH ×BC= 1/2 ×12,9×32,27=208,1415
A because 40% of 3500 is 40%
Answer: a. gregory b. linus
step by step explanation:
V= 3 x 4^2 x 12
v= 576cm^3
TheThe area of the shaded region if the radius of the outer circle is 4 and the radius of the inner circle is 2 is 12π.
<h3>Area of the shaded region</h3>
Area of a circle = πr²
r =radius of the circle
Area of the outer circle:
Area of the outer circle = π(4)²
Area of the outer circle = 16π
Area of the inner circle:
Area of the inner circle = π (2)²
Area of the inner circle = 4 π
Area of the shaded Region :
Area of the shaded Region = 16π - 4 π
Area of the shaded Region = 12π
Therefore the area of the shaded region if the radius of the outer circle is 4 and the radius of the inner circle is 2 is 12π.
Learn more about area of the shaded region here: brainly.com/question/19577281
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