Equations as intersections

The solutions of \(f(x)=g(x)\) are the \(x\)-coordinates where \(y=f(x)\) and \(y=g(x)\) meet. A curve crossing the \(x\)-axis solves \(f(x)=0\); meeting the horizontal line \(y=k\) solves \(f(x)=k\).

Here the solid curve is \(y=x^2\) and the dashed line is \(y=x+2\). Their intersections give \(x=-1\) and \(x=2\).

When an equation is rearranged to use a supplied curve, keep that curve on one side and identify the line to draw on the other. Check that every required intersection lies inside the displayed interval.