a8+a4=24,a6+a10=34.find common difference and first term
Answers
a+7d+a+3d = 24
a+5d = 12. (1)
A6 = 12.
a+5d+a+9d = 34
a+9d = 34-12
a+9d = 22. (2)
(2)-(1)
4d = 10
d = 5/2
a = 12-5d
= 12-12.5
= -1/2
hope it helped you
please mark it as the brainliest answer
Given :
a8 + a4 = 24
and
a6 + a10 = 34
To find:
common difference (d ) and first term (a)
Solution:
we know that
a8= a+7d and
a4= a+3d
from given equations
(a+7d)+(a+3d) = 24
2a+10d = 24 -----(1)
similarly,
a6= a+5d &
a10= a+ 9d
(a+5d)+ (a+9d) = 34
2a+ 14d=34 -----(2)
By using elimination method
2a+10d=24
2a+14d=34
- - -
(2a will be canceled)
we will get
-4d = -10
d = 10/4
d= 5/2
d= 2.5
put d = 2.5 in eq (1)
2a + 10 × 2.5 =24
2a + 25 = 24
2a + 25= 24
2a = 24-25
a = -1/2
a = -1/2
Hence, common difference = 5/2 or 2.5 and first term = -1/2 or -0.5
If it helps you then Mark as brainliest.