This is quite easy as it is simply knowing the formulas to solve different portions of the circle.
(A) To solve for circumference, the formula is d*pi where d is the diameter. The diameter is simply twice the radius, so we can just double 11 for it. This means 22 is the answer.
(B) The formula for area of a circle is pi*r^2, so for this one, we just need to square the radius. 11 squared is 121.
(C) To solve this, we should solve for the area of the circle, and then multiply it by 3 to represent the 3 dollars. To solve the area, we just substitute 11 into the formula for r. Afterwards, we should multiply it by 3 for the reason above. However, because we used 3.14 instead of pi, we must say the cost is approximately $1139.82. <span />
Sec θ = 3
1/cos θ = 3
1/sin(90 - θ) = 3
csc(90 - θ) = 3
Hey there! I'm happy to help!
Let's call the length and width L and W respectively.
L=2W+8
2W+2L=124
We plug our value of L into the second equation and solve for W.
2W+2(2W+8)=124
We undo the parentheses with the distributive property.
2W+4W+16=124
Combine like terms.
6W+16=124
Subtract 16 from both sides.
6W=108
Divide both sides by 6.
W=18
We plug this W value into the first equation to solve for L.
L=2(18)+8
L=36+8
L=44
So, the length is 44 feet and the width is 18 feet.
Have a wonderful day! :D