X-3=14
+3 +3
x=17
x-3=-14
+3 +3
x=-11
B and c are the factors because they make the product
A half-life of the isotope is 15 days and at start its mass is 32 g.
A table:
t: m:
0 32 g
15 16 g
30 8 g
45 4 g
60 2 g
75 1 g
In the first column is used an arithmetic sequence ( a 1 = 0, d = 15 ).
In the second column is used a geometric sequence ( a 1 = 32, r = 1/2 )
3. Banks use interest in order to make a cut of the money.
