It’s 2 my work is in the picture
The Rnge of f(x)=1/7(9)^x is 0 to infinty
y|y>0
X = # 0.75 stamps y = # 0.45 stamps total postage = $5.70
I really hope that helps cause I went all out and best of wishes!!
x f(X) g(x)2.5 2 1.25
1.5 0 -2.75
2.75 2.5 2.56
2.8 2.6 2.84
2.77 2.54 2.67
2.73 2.46 2.45 <<<<<<< Answer.
I've included a graph to show you another way that you could get closer quicker.
The red line is y = 2x - 3
The blue line is y = x^2 - 5