1. given
2. measure angle 1 plus measure angle 2 equals 90 degrees
3. B D bisects angle A D C
4. definition of angle bisector
5. definition of congruence
6. measure angle 1 is equal to measure angle 3
7. angle 1 is congruent to angle 3
7. definition of congruence
hope that helps
I'm assuming this is multiple choice and you forgot to post the answers. I'll take a guess and say it probably looks something like this:

Because you can't take the square root of a negative number without getting an imaginary result, resulting in the function having a closed domain limit.
To complete the square you must split the b term in half, then square that answer.
6 is the b term, half of 6 is 3, 3 squared is 9. You will add 9 to both sides of x^2 + 6x = 15
x^2 + 6x + 9 = 24
Each of the toppings cost 2$
(-3,-10).....slope(m) = 2
y - y1 = m(x - x1)
y - 3 = 2(x - 10)