the answer is b. I'm pretty sure at least because the square root it roughly 5.91 and that's between 5 and 6.
T_n = 3 * T_(n-1)
Long way (always works!)
T_5 = 3*T_4,
T_4 = 3*T_3
T_3 = 3*T_2
T_2 = 3*T_1
T_5 = 3*3*3*3*T_1 = 81*T_1 = 81*8 = 648!
Short way (sometimes it works!)
T_n = 3^(n-1) * T_1 (this case is a geometric series of ratio-=3)
T_5 = 3^4*8 = 648
I'm sure you should look it up on Google I'm pretty sure that that would help you more than this stupid app OK look it up on Google or a Siri it will help you a lot better
5x - 3y = -11 (×2)
2x - 6y = -14 (x5)
10x - 6y = -22
10x - 30y = -70
---------------------- -
24y = 48
y = 2