Answer:n= (-217)
Step-by-step explanation:
-3(2n+7)=1281 first distribute the -3
-6n-21=1281
then add 21 to the right side the isolate the variable
-6n=1302
divide 1302 by -6
n= -217
Doubling time

A=final amount
P=initial amount
n=number of days
d=number of days to double
so
given initial is 40 ants
doubling time is 10 days
and days we want is 20 then



A=160
the population is 160