3x^2-5x+12
5x^2+x-11
3x^2-5x+12
-(5x^2+x-11)
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3x^2-5x+12
-5x^2-x+ 11
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-2x^2 -6x+23
Answer:1 hr and 25 minutes
Step-by-step explanation:add 3:15 with 30 min to get 3:45 then add 4:50 with 30 minutes to get 5:20
Hopefully this helps ^_^ part c is longer then 6:30