Answer:
a = - 4, b = 5
Step-by-step explanation:
Expand the left side and compare the coefficients of like terms on the right side.
- 3(2x² + ax + b)
= - 6x² - 3ax - 3b
Comparing like terms with - 6x² + 12x - 15
x - term → - 3a = 12 ( divide both sides by - 3 )
a = - 4
constant term → - 3b = - 15 ( divide both sides by - 3 )
b = 5
Answer:
ΔEFG is an isosceles triangle.
Step-by-step explanation:
Given:
E (0, 0),
F (−7, 4),
G (0, 8)
ΔEFG
Solution:
Distance formula
Distance d = 
Step 1: Finding the length of EF
By using distance formula,



Step 2: Finding the length of FG
By using distance formula,

Step 2: Finding the length of GE

Thus we could see that the sides EF = FG
So it is a isosceles triangle.
Refer to the diagram shown below.
The directrix is y = -4 and the focus is (-2, -2).
Therefore the vertex is at (-2, -3).
Consider an arbitrary point (x,y) on the parabola.
The square of distance from the focus to the point is
(x+2)² + (y+2)²
The square of the distance from the point to the directrix is
(y+4)²
Therefore
(y+4)² = (y+2)² + (x+2)²
y² + 8y + 16 = y² + 4y + 4 + (x+2)²
4y = (x+2)² - 12
y = (1/4)(x+2)² - 3
Answer: