How do you write an exponential function of the form y = a b^x the graph of which passes through (-1, 4/5) and (2, 100)?
1 Answer
Jun 12, 2016
Explanation:
Plug in
For
#4/5=a(b)^-1" "" "bb((1))#
and for
#100=a(b)^2" "" "bb((2))#
Note that
#4/5=a/b" "" "bb((3))#
We can solve for
#4/5b=a#
We can use
#100=a(b)^2" "=>" "100=4/5b(b)^2#
We can now solve this for
#100=4/5b^3#
Multiplying both sides by
#125=b^3#
#b=5#
Returning to
#4/5=a/b" "=>" "4/5=a/5" "=>" "a=4#