Emma drank three 8 ounce cups of coffee. each cup of coffee contains 130 mg of caffeine. emma's body elimantes 13% of the caffeine each hour. write an exponential function that represents the amount of caffeine, c , in her body after t hours.

So ok

reduced by 13% each times 100-13=87 so 87 % of previous

so

t=time elapsed
I=initial amount
C=future amount
C=I(percentrate)^t

so

Do the math. she originally had 50 dollars on her gift card and she had 12 dollars left on her gift card after she finished her shopping spree. if you subtract 50 minus 12 you get thirty eight dollars as your answer. so therefore, ciara spent 38 dollars total o

First subtract 10 from both side
y^2+6y-16=0
(y+8)(y-2)=0
-8 and 2