Step-by-step explanation:
2 (t-3)²- 72 = 0
2 (t²-6t+9) -72 = 0
2t² - 12t +18 -72 = 0
2t²-12t-54=0
2(t²-6t-27) ; divide both sides by 2
t²-6t-27=0 ; factor
(t+3) (t-9)
transpose,
t = - 3
t = 9
