2x, 5, 6-x are first 3 terms of an A.P.Find the 10th term.
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a1=2x, a2 =5, a3=6-x are first three terms in an AP
a2 - a1 = a3 - a2
5-2x= 6-x -5
5-2x=1-x
5-1=2x-x
4=x
x=4
therefore
a1=2x=2×4=8
a2=5
a3=6-x=6-4=2
first term=a=a1=8
common difference =d=a2-a1=5-8=-3
an = a+(n-1)d
a10= 8+(10-1)(-3)
a10=8+9×(-3)
=8-27
=-19
a2 - a1 = a3 - a2
5-2x= 6-x -5
5-2x=1-x
5-1=2x-x
4=x
x=4
therefore
a1=2x=2×4=8
a2=5
a3=6-x=6-4=2
first term=a=a1=8
common difference =d=a2-a1=5-8=-3
an = a+(n-1)d
a10= 8+(10-1)(-3)
a10=8+9×(-3)
=8-27
=-19
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