Discrepancy with Toricellis equation in a 2D kinematics prob

[CherryWine]

Homework Statement

A stone is thrown from a height 2.1m with an angle of 45 degrees. It fell to the ground 42 m from the throwing position, measured horizontally. Initial velocity is 19,81 m/s, flight time is 3s what is the maximum height?

Homework Equations

All 2D kinematics equations.

The Attempt at a Solution

I plugged in the variables into the equation y(t), and equated Vfin=0, for the maximum height and obtained the correct result which should be 10m from the starting position and 12,1m from the ground. But when I tried to solve the problem using equation Vfin^2=V0^2+2gΔy I obtain 20m which is not correct. Why is it not correct?

 

[TSny]

But when I tried to solve the problem using equation Vfin^2=V0^2+2gΔy I obtain 20m which is not correct. Why is it not correct?

You will need to show more of your work in order for us to find the error. Are the velocities in this equation supposed to be y-components of velocity?

 

[CherryWine]

You will need to show more of your work in order for us to find the error. Are the velocities in this equation supposed to be y-components of velocity?

Thank you very much! It was my careless mistake. I didn't use y-components of velocity. Thank you! Turns out to be consistent. Thanks again.