Jawapan

  • Pengguna Brainly
2016-01-10T11:51:53+08:00
T6=20
S6=210
T1=? , d=?

T6=20
20=a + 5d
a=20 - 5d

S6=210
210=3(2(20-5d) + 5d
210=3(40 - 10d) + 5d
210=120 - 30d + 5d
30d - 5d=120-210
25d=-90
d=-18/5

a=20-5(-18/5)
a=20 + 18
a=38
T1=a
T1=38
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