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Write an exponential function in the form y(0, 20) and (3, 1280).abl that goes through points

User Glmxndr
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1 Answer

18 votes
18 votes

the general form of the exponential function is


y=a^x+b

first replace (0,20)


\begin{gathered} 20=a^0+b \\ 20=1+b \\ b=20-1=19 \end{gathered}

for now, the formula is


y=a^x+19

now, replace (3,1280)


\begin{gathered} y=a^x+19 \\ 1280=a^3+19 \\ a^3=1280-19 \\ a^3=1261 \end{gathered}
a=\sqrt[3]{1261}=10.8

so, the exponential function is


y=10.8^x+19

User Expert Wanna Be
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