Answer:
5th term = 18
Step-by-step explanation:
a1 + a1+d a1 + 2*d a1+3d a1 + 4*d a1 + 5d
a1 + 2d = 10
6*a1 + 15d = 72
Multiply the first equation by 6
6a1 + 12d = 60
Write the above equation underneath the second equation
6a1 + 15d = 72
6a1 + 12d = 60 Subtract
3*d = 12 Divide by 3
d = 12/3
d = 4
a1 + 2d = 10
a1 + 2*4 = 10
a1 + 8 = 10 Subtract 8 from both sides
a1 - 8 = 10- 8
a1 = 2
The fifth term is
t5 = 2 + 4*4
t5 = 18
