Question

8
. Find the value of unknown angle y in the following figure:
A
65
B/40° YAC
.
.​

Answer 1

Answer:

Given,

a=12,d=6,a

n

=252

a

n

=a+(n−1)d

252=12+(n−1)6

40=n−1

∴n=41

S

n

=

2

n(a+a

n

)

=

2

41(12+252)

=5412