The decay of 277 mg of an isotope is described by the function A(t)= 277e^0.019t , where t is time in years. Find the amount left after 64 years. Round your answer to the nearest mg. Show all of your work for full credit.

The decay of 277 mg of an isotope is described by the function

A(t)= 277e-0.019t,

where t is time in years.

To find the amount left after 64 years,

We substitute t = 64 in the expression.

A(t=64)= 277e-0.019(64)

or A(t=64) = 277 * e-1.216

                = 277 * 0.29

                = 82 mg

thats not a system of equations, that is a solution