It gives function: h = -16t^2 + 40
water is when height is 0 so solve for 0= -16t^2 + 40
subtract 40 from both sides: -40 = -16t^2
divide by -16: -40/-16 = t^2
simplify: 5/2 = t^2
square root both sides: 1.58 = t
the orange hits the river in 1.58 seconds.
3x=90 2x=50
And the last one is 40
