If it's just distribution, not solving for s (I mean I could but do you need to?):
5(2s² - 3s + 4) Distribute/multiply 5 into (2s² - 3s + 4)
(5)2s² - (5)3s + (5)4
10s² - 15s + 20
(88sin20)(t - 16t²) = 0
(8(0.3090169944)(t - 16t²) = 0
(2.472135955)(t - 16t²) = 0
2.472135955t - 39.55417528t² = 0
The answer is 2/3 or 0.66666...
8.6*7=60.2, 16*1.4=22.4, 12*14=168, 7.3*20=146