800 + 16x = 720 + 21x. Cancel out the 720 to get 80 + 16x = 21x. Subtract 16x from both sides to get 80 = 5x. Divide by 5 to get 16 = x, or x = 16. 16 hours. The charge is 800 + 16(16), = 720 + 21(16) which = 800 + 256 = 720 + 336 which = 1,056 = 1,056. Hope this helped!
Answer:
So for number 1 we can use the trigonometry to find out the radius/diameter of the circle then we can use the formula to get the area then we divide by 2 because its half of a circle. So we can get that the cos(68) = 7/x x being the diameter. We then can multiply it by x on both sides. That gives xcos(68) = 7. So then we can do the inverse and get x = cos^-1(68)*7. That gives us approx 18.686 as the diameter, we can divide by 2 and get 9.343. So then we can use the formula which is A = pi*r^2. So that gives us 87.291*pi 274.233. Then if we divide by 2 we get 137.12 that is the answer to first question.
I was able to simplify it into the factored form for number 2.(x-1)^2+(y-2)^2=sqrt(17))^2. Therefore using the circle equation formula we can determine that the center is 1,2. The radius is sqrt(17). We square it and we get 17. So that means that the area is pi*17. Then we get 51.407 as the area.
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Answer to 1: 137.12 round to tenth and you get 137.1</u></h2><h2><u>
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Answer to 2: </u></h2><h2><u>
Center: 1,2 </u></h2><h2><u>
Area: 51.407.</u></h2>
