The number of tangents from an external point $P$, constrained to a parabola, to the branches of a given hyperbola $B$

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Consider the hyperbola $B:\frac{(x-7)^2}{4}-\frac{(y+3)^2}{9}=1.$ A variable point $P(\alpha+7,\alpha^2-4)$ where $\alpha$ belongs to ${\Bbb R}$ exists in the $xy$-plane.

Let $B_{\rm left}$ and $B_{\rm right}$ be the left and right branches of the given hyperbola $B$.

Q1. The values of $\alpha$ for which two distinct real tangents can be drawn to $B_{\rm left}$ from $P$?

(Answer is $\alpha= -1$ [I think this is insufficient:

It should be an open interval containing $-1.$

--JM])

Q2. The values of $\alpha$ for which only one real tangent can be drawn to $B_{\rm left}$ only from point $P$?

(Answers are $\alpha= -2,-\frac12$)

Q3. The values of $\alpha$ for which two real tangents can be drawn to $B_{\rm right}$ only from point $P$?

(Answer is $\alpha=2$ [I think this is wrong:

It should be an open interval ending in but not containing $2.$

--JM])

These are the subparts which have to be solved from the data given above.

Is there any condition that should be satisfied in order to solve the question?

I am not able to form the inequalities to get the solution set for $\alpha.$

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Hint: use geogebra to get intuition

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