1 hour = 450 calories
------------------------------------------
Rewrite 1 hour as 60 mins :
------------------------------------------
60 mins = 450 calories
------------------------------------------
Divide by 3 through :
------------------------------------------
20 mins = 450 ÷ 3
20 mins = 150 calories
------------------------------------------------------------------------------------
Answer: 20 mins burns 150 calories.
------------------------------------------------------------------------------------
Hello,
2x²+x-14=0
Δ=1+4*14*2=113
x=(-1-√113)/4=-2,8839...≈-2.88
or x=(-1+√113)/4=2,40753≈2.41