Solve the following math problem efficiently and clearly:

- For simple problems (2 steps or fewer):
Provide a concise solution with minimal explanation.

- For complex problems (3 steps or more):
Use this step-by-step format:

## Step 1: [Concise description]
[Brief explanation and calculations]

## Step 2: [Concise description]
[Brief explanation and calculations]

...

Regardless of the approach, always conclude with:

Therefore, the final answer is: $oxed{answer}$. I hope it is correct.

Where [answer] is just the final number or expression that solves the problem.

Problem: In triangle $ABC$, angle $ACB$ is 50 degrees, and angle $CBA$ is 70 degrees.  Let $D$ be the foot of the perpendicular from $A$ to $BC$, $O$ the center of the circle circumscribed about triangle $ABC$, and $E$ the other end of the diameter which goes through $A$.  Find the angle $DAE$, in degrees.

[asy]

unitsize(1.5 cm);

pair A, B, C, D, E, O;

A = dir(90);

B = dir(90 + 100);

C = dir(90 - 140);

D = (A + reflect(B,C)*(A))/2;

E = -A;

O = (0,0);

draw(Circle(O,1));

draw(A--B--C--cycle);

draw(A--D);

draw(A--E,dashed);

label("$A$", A, N);

label("$B$", B, W);

label("$C$", C, SE);

label("$D$", D, SW);

label("$E$", E, S);

dot("$O$", O, dir(0));

[/asy]
user