The answer is answer choice 3
Multiply by 2 which will get you a diameter and then multiply it by pi which is 3.14.
it is going to take 18 miles in 1 hour
3a + 6b = 45
2a - 2b = -12....multiply by 3
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3a + 6b = 45
6a - 6b = - 36 ...(result of multiplying by 3)
---------------add
9a = 9
a = 1
3a + 6b = 45
3(1) + 6b = 45
3 + 6b = 45
6b = 45 - 3
6b = 42
b = 7
solution is : (1,7)
