However, if you don't want to input coefficients and just use the Y= vars directly, then it gets a bit complicated. Still doable though! The first thing you need to do is evaluate Y2-Y1 at three points. For convenience, we'll do -1, 0, and 1. From these three points, we can construct the coefficients:

Evaluate the three points:

`Y1(⁻1)-Y2(⁻1→A Y1(0)-Y2(0→B Y1(1)-Y2(1→C`

Interpolate to get the coefficients:

`.5(C-A→D 2(Ans+A-B→A`

(The quadratic equation is AX²/2+DX+B)

Now we just do our standard quadratic solver, but we'll add some safety checks:

`If A:Then D²-2AB If Ans<0 Ans+0i √(Ans→B Disp (D-B)/A,(D+B)/A Else If D=0:Then If B=0:Then Disp "INTERCEPTS EVERYWHERE Else Disp "INTERCEPTS NOWHERE End Else Disp ⁻B/D End End`

**NOTE:** This only works if Y1 and Y2 are quadratic (i.e., ax²+bx+c, but a and/or b are allowed to be 0)

There may be easier ways on the newer calcs, I'm not sure, but this should work either way :)

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