If you add positive 5 and positive 5, you'll get positive 10.
If you add positive 5 and negative 5, you'll get positive 0.
If you add negative 5 and negative 5, you'll get negative 10.
-5 + 5 = -5 + 5
5 + 5 = 5 + 5
- 5 + -5 = -5 + -5
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Answer:
the chances of rolling a 3 are 1/6
the changes of not doing it is 5/6
4(y - 7) = 2y - 38
4y - 28 = 2y - 38
4y - 2y = -38 + 28
2y = -10
y = -5
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.
