Easy, just divide
kelly=440mi/8hr=220mi/4hr=110mi/2hr=55mi/1hr
alberto=468mi/9hr=156mi/3hr=52mi/1hr
55>52
kelly drove 55mi in 1 hour
55-52=3
she drove 3 miles more in 1 hour

A linear function has 1 as the highest power of the variable.
A. f(x) = 2 - 7x
here, the highest power of the variable x is 1.
Hence it is a LINEAR function.
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B. f(x) = 2 + x + x^2
here, the highest power of the variable x is 2.
Hence it is NOT a linear function.
_______________

here, the highest power of the variable x is 1/2.
Hence it is NOT a linear function.
________________
2/9 divided by 1/2. invert the second fraction and multiply
2/9 * 2/1 = 4/9
If Tim is 2 more than twice angies age, Tim is 42.
I belive there is none because it lands on the origin for y.