How am I supposed to expand $\sin^2 A + \sin^4 A = 1$ into $1 + \sin^2A = \tan^2A$? My question is how can i expand
$$\sin^2 A + \sin^4 A = 1$$
into:
$$1 + \sin^2A = \tan^2A$$
I tried quite a few ways I know but all of them kinda felt random. i am not sure how to share my trials here. I am quite beginner in trigonometry. it is one of the extra test question from my textbook. I don't need it but cant control curiosity. so pls help me.
Thanks in advance!
EDIT:
found the solution, dropping it here, 
\begin{align}
\sin^2 A + \sin^4 A & = 1 \\
\sin^4 A & = 1 - sin^2 A \\
\sin^2 A . \sin^2 A & = cos^2 A \\
\sin^2 A . (1 - \cos^2 A) & = cos^2 A \\
\sin^2 A - \sin^2 A.\cos^2 A & = cos^2 A \\
\sin^2 A & = cos^2 A + \sin^2 A.\cos^2 A \\
\sin^2 A & = \cos^2 A(1 + \sin^2 A) \\
1 + \sin^2 A & = \cfrac{\sin^2 A}{\cos^2 A} \\
1 + \sin^2 A & = \tan^2 A \\
\end{align}

Hint
If $\sin^2A + \sin^4A = 1 \implies \sin^4A = \cos^2 A$
Can you proceed from here?
Additional Info
$$\sin^2A(1-\cos^2A) = \cos^2A$$
$$\sin^2A = \cos^2A + \sin^2A\cos^2A$$
Divide by $\cos^2 A$
