Question

If the third and the sixth term if an ap is 7 and 13 respectively . Find the 10th term

Answer 1

so , this is the answer ,
.
.
A3 = a + 2d = 7
A6 =a + 5d = 13
from 2 equation and 2variable
3d = 6
d = 2
therefore,
$a + 2(2) = 7$
$a + 4 = 7$
$a \: = 3$
so A10 = a + 9d
3 + 9(2)
3 + 18
21 is the 10 th term of AP