Answer:
.5
Step-by-step explanation:
Plug in a point on the line. Let us take (-1,2).
When you plug it in, you get:
2 = [tex]b^{-1}[/tex]-->
2 = 1/b -->
b = .5
y=b^x
when x=-2,y=4
4=b^{-2}
b^2=1/4
b=√(1/4)=1/2=0.5
