Complete the square:
F(x) = -3x² - 6x - 5
F(x) = -3 (x² + 2x) - 5
F(x) = -3 (x² + 2x + 1 - 1) - 5
F(x) = -3 ((x + 1)² - 1) - 5
F(x) = -3 (x + 1)² + 3 - 5
F(x) = -3 (x + 1)² - 2
The y-intercept has x-coordinate equal to 0, so it corresponds to the value of F(0) :
F(0) = -3 (0 + 1)² - 2 = -3 - 2 = -5
The axis of symmetry is the vertical line running through the vertex of this parabola, so we'll come back to this.
The vertex of the parabola is (-1, -2). This represents the maximum value of F(x), which follows from
(x + 1)² ≥ 0 ⇒ -3 (x + 1)² ≤ 0 ⇒ -3 (x + 1)² - 2 ≤ -2
This is to say, every point on the parabola has a y-coordinate no greater than -2.
As mentioned earlier, the axis of symmetry is the vertical line through the vertex, and its equation is determined by the x-coordinate of the vertex. Hence the AoS is the line x = -1.
Answer: B. (Leah did not have to provide collateral.)
Answer: Independent
Step-by-step explanation: Just multiply the probability of the first event by the second.
Given:
must correctly answer 80% of the questions
correctly answered questions = 26
incorrectly answered questions = 4
unanswered questions = 15
Total questions = 26 + 4 + 15 = 45
45 * 80% = 36 required correctly answered questions.
36 - 26 = 10
Out of 15 remaining questions, 10 questions must be correctly answered for Heidi to advance to the next level.
