a6=17
S16=392
a9
S16=(2a1+15d)16/2=392
a6=a1+5d=17
a1=17-5d
S16=(2(17-5d)+15d)*16 =784
d=3
a1=17-15=2
a9=2+8*3=26
a6=a1+5d=17S16=(2a1+15d)/2 * 16 = (2a1+15d)8 = 392{a1+5d=17{(2a1+15d)8=392{a1+5d=17 => a1=17-5d{2a1+15d=492(17-5d)+15d=4934-10d+15d=495d=15d=3a1=17-15=2a9=a1+8d=2+24=26
a6=17
S16=392
a9
S16=(2a1+15d)16/2=392
a6=a1+5d=17
a1=17-5d
S16=(2(17-5d)+15d)*16 =784
d=3
a1=17-15=2
a9=2+8*3=26
a6=a1+5d=17
S16=(2a1+15d)/2 * 16 = (2a1+15d)8 = 392
{a1+5d=17
{(2a1+15d)8=392
{a1+5d=17 => a1=17-5d
{2a1+15d=49
2(17-5d)+15d=49
34-10d+15d=49
5d=15
d=3
a1=17-15=2
a9=a1+8d=2+24=26