3t+11 = 29 3t = 29-11 3t = 18 t = 6
4+3t = 22 3t = 22-4 t = (22-4)/3 t = 6
-12t+4
S = 3 st + 3t = 6 st = 6 - 3t s = (6 - 3t)/t = 6/t - 3
In 2t+8 19
3t+11 = 29 3t = 29-11 3t = 18 t = 6
s = 7, t = -3
4+3t = 22 3t = 22-4 t = (22-4)/3 t = 6
3t + 7 = 2t - 5 3t = 2t - 12 t = -12
-12t+4
S = 3 st + 3t = 6 st = 6 - 3t s = (6 - 3t)/t = 6/t - 3
8
In 2t+8 19
t = -11/10
15t+25 = 5(3t+5)
Yes and t = 1 in both equations
Commutatitivity of addition in the fact that you can change the order of 11s and 3t. But also associativity of addition in that you can write the sum of three terms without the need for brackets to show which addition needs to be performed first.