Answer:
- a) - 8 and 2
- b) (- 3, - 75)
Step-by-step explanation:
Given relation
a)
Find its zero's
- 3x² + 18x - 48 = 0
- x² + 6x - 16 = 0
- x² + 8x - 2x - 16 = 0
- x(x + 8) - 2(x + 8) = 0
- (x + 8)(x - 2) = 0
- x + 8 = 0 ⇒ x = - 8
- x - 2 = 0 ⇒ x = 2
b)
The vertex of qudratic function is determined at x = - b/(2a)
Applied to this relation, the x- coordinate of vertex is
- x = - 18/(3*2) = - 18/6 = - 3
Find its y- coordinate
- y = 3(-3)² + 18(-3) - 48 = 27 - 54 - 48 = -75
The vertex is (- 3, - 75)
