Answer:

Step-by-step explanation:
1st boat:
Parabola equation:

The x-coordinate of the vertex:

Equation:

The y-coordinate of the vertex:

Parabola passes through the point (-8,1), so

Solve:

Parabola equation:

2nd boat:
Parabola equation:

The x-coordinate of the vertex:

Equation:

The y-coordinate of the vertex:

Parabola passes through the point (-8,1), so

Solve:

Parabola equation:

System of two equations:

This would be something like [5] or -[-5] which is absolute value (>.<)
Answer:
D
Step-by-step explanation:
The external angle of a triangle is equal to the sum of the 2 opposite interior angles.
∠ BCD is an exterior angle of the triangle, thus
∠ BCD = 50° + 60 = 110° → D
Answer:
I think they are all letter A
Step-by-step explanation: