If sum of the 3rd and 8th term of an ap is 7 and the sum of the 7th and 14th term is -3.find the 10th term
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⚫A3+a8=7
A+2d+a+7d=7
2a+9d=7 (1)
⚫A7+a17=-3
A+6d+a+16d=-3
2a+19d=-3 (2)
By subtraction of eq (1)&(2)
2a+9d=7
2a+19d=-3
- - -
----------------
10d=10,d=1
⚫Now put the value of d=1 in eq (1)
2a+9d=7
2a=7-9(1)
2a=-2,a=-1
A10=a +9d
A10=-1+9(1)
⚫A10=8
So 10th term is 8
Hope it's help you friend ☺️
A+2d+a+7d=7
2a+9d=7 (1)
⚫A7+a17=-3
A+6d+a+16d=-3
2a+19d=-3 (2)
By subtraction of eq (1)&(2)
2a+9d=7
2a+19d=-3
- - -
----------------
10d=10,d=1
⚫Now put the value of d=1 in eq (1)
2a+9d=7
2a=7-9(1)
2a=-2,a=-1
A10=a +9d
A10=-1+9(1)
⚫A10=8
So 10th term is 8
Hope it's help you friend ☺️
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