Answer:
9/4
Step-by-step explanation:
[tex] - 16 {t}^{2} + 28t + 18 = 0[/tex]
[tex] {t}^{2} - \frac{7}{4} t - \frac{9}{8} = 0[/tex]
[tex] {t}^{2} - \frac{7}{4} t = \frac{9}{8} [/tex]
[tex] {t}^{2} - \frac{7}{4} + \frac{49}{64} = \frac{9}{8} + \frac{49}{64} [/tex]
[tex](t - \frac{7}{8} ) {}^{2} = \frac{121}{64} [/tex]
[tex]t - \frac{7}{8} = ± \frac{11}{8} [/tex]
[tex]t = \frac{18}{8} = \frac{9}{4} [/tex]
