2(t+3)+7(t-3)=5(t-1)?

Bab Aljabar
Matematika SMP Kelas IX

2(t + 3) + 7(t - 3) = 5(t - 1)
2t + 6 + 7t - 21 = 5t - 5
9t - 5t = 5 + 15
4t = 20
t = 20/4
t = 5

2 (t+3) + 7 (t-3) = 5 (t-1)
2t + 6 + 7t - 21 = 5t - 5
9t - 15 = 5t - 5
9t - 5t = -5 + 15
4t = 10
t = 10/4
t = 5/2
t = 2,5