kakkak tolong dijwb plissss kak bsk dikumpul!!!plisss::')

6) a) 16+19+22+.....
b= 19-16
= 3
U10= a+(n-1)b
= 16+(10-1)3
= 16+(9)3
= 16+27
= 43
b) 30+26+22+....
b= 26-30
= -4
U10= a+(n-1)b
= 30+(10-1)-4
= 30+ (9)-4
= 30+ (-36)
= -6