Cartesian Form/basic quadratic question

[sick dragon]

why does the graph cross x axis at +-1/2 and not 1?(ik i am being very stupid)

[coral pollen]

x=t/2
2x=t
4x^2 = t^2

y=1-t^2
y=1-4x^2
Solving for roots set y to 0
0=1-4x^2
4x^2 = 1
x^2 = 1/4
x = +/- 1/2

[sick dragon]

oh i forgot to root