Question 612902
{{{y = a*b^x}}}


{{{5 = a*b^(1)}}}


{{{5/(b) = a}}}


{{{a = 5/(b)}}}



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{{{y = a*b^x}}}


{{{7 = (5/(b))*b^(2)}}}


{{{7 = 5b^(2 - 1)}}}


{{{7 = 5b}}}


{{{7/5 = b}}}


{{{b = 7/5}}}



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{{{y = a*b^x}}}


{{{y = a*(7/5)^x}}}


{{{5 = a*(7/5)^(1)}}}


{{{5 = a(7/5)}}}


{{{5*5 = 7a}}}


{{{25 = 7a}}}


{{{25/7 = a}}}


{{{a = 25/7}}}



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{{{y = a*b^x}}}


{{{y = (25/7)*(7/5)^x}}}



So the exponential equation in the form {{{y=ab^x}}} that passes through (1,5) and (2,7) is {{{y = (25/7)*(7/5)^x}}}