Answer:
Step-by-step explanation:
Vertex form of a quadratic equation;
Vertex of the parabolas (h, k)
The vertex of the parabola is either the minimum or maximum of the parabola. The axis of symmetry goes through the x-coordinate of the vertex, hence h = -3. The minimum of the parabola is the y-coordinate of the vertex, so k= 7. Now substitute it into the formula;
Now substitute in the given point; ( -1, 9) and solve for a;
Hence the equation in vertex form is;
In standard form it is;
Answer: 
Step-by-step explanation:
Given
The tower is at a height of 
the angle of depression is 
Suppose the surfer is x ft away from the base of the tower
Therefore, the surfer is at a distance of 19.31 ft from the base of the tower.
First, it would help to put 46 and 2/3 into an improper fraction: 140/3.
Then, since this is a percent, we put that improper fraction over 100: (140/3)/100 = 140/300.
Finally, we multiply this answer by 28 since "of" means multiply:
(140/300) * 28 = 196/15 = 13 1/15
Answer:
Draw the triangle.
Draw the perpendicular bisector to each side of the triangle. Draw the lines long enough so that you see a point of intersection of all three lines.
Draw the circle with radius at the intersection point of the bisectors that passes through one of the vertices
12×4=48 , 68×12 is a much greater number.
