The answer is 4. I hope this helped.
Center is at (h,k) in standard form:
(x-h)2 + (y-k)2 = r2
Center: (-8, -3)
Radius (r): sr49 = 7
A point on the graph (for train b) that is exact is (2,250). From the origin, the rise is 250 and the run is 2. Rise/run would give us 250/2, which is 125. This means that train B travels 125mi every hour. For train A, we subtract the distance from hour 2 from hour 3 to get the miles per hour (because 3-2=1, subtracting the distance of hour 3 from 2 will give us the distance in 1 hour). 180-120= 60, meaning train A travels at 60mph. 60<125, meaning A
5^4
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5^6
625
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15,625
625/15625=25
1 7/9 divided by 2/9 is 8 hunny hope it helps ^_^