You add $5.38 & $15.95, which equals $21.33. Then subtract $21.33 from $38.12. Your answer is $16.79. That's how much Shane spent on the book.
The flags are a translation. Both flags are located at different origins, so it couldn't be a rotation. Both flags have the colors in the same place ( black on the bottom, white on the top) so one flag was moved up or down from the other flag, which is a translation.
-4.9t²+7.5t+1.8=2.1
-4.9t²+7.5t-0.3=0
t=-7.5±√(56.25-4*-4.9*-.3)/-2*4.9
t=-7.5±√(44.49/-9.8
t=(-7.5±6.67)/-9.8
t=-.83/-9.8 = .085 or t= -14.17/-9.8 = 1.446
