Kaylee needed to write the equation of an exponential function from points on the graph of the function. To determine the value of b, Kaylee chose the ordered pairs (1, 7) and (3, 42) and divided 42 by 7. She determined that the value of b was 6. What error did Kaylee make? Complete the explanation. The value Kaylee found is not the constant ratio of successive values. She should use ordered pairs with x-values that differ by

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