Could you help me please with the following problem.
For each set of functions, indicate its mathematical expression:
a) parabolas that pass through the origin and the point $(1,1)$
b) circles tangent to the x-axis and whose center is over the line $x = 1$
Edit
For the parabolas I got $c=0$ and $a+b=1$.
HINT
Start from the general standard equations for
parabolas: $y=ax^2+bx+c$
circle: $(x-x_c)^2+(y-y_c)^2=R^2$
and apply the given conditions.
For the parabolas since we got $c=0$ and $a+b=1$, the general equation is
$$y=ax^2+(1-a)x, \, a \in \mathbb R$$