A carpet is thrown upwards and its height h metres after t seconds is given by the formula h=35r-5r^2. How long does it take to reach a height of 50m? Explain the meaning of the double answer

assuming you meant

h = 35t-5t^2, then just solve

35t-5t^2 = 50

If you get two answers, then that is because the carpet went up higher than 50 meters, and then came back down.

I must say, throwing a carpet up more than 50 meters is quite a feat! Was it shot from a cannon?