Answer:
Step-by-step explanation:
Because the vertex of the parabola is at (16,0), its equation is of the formy = a(x-10)² + 15
The graph goes through (0,0), thereforea(0 - 10)² + 15 = 0100a = -15a = -0.15
The equation is y = f(x) = -0.15(x - 10)² + 15
The graph is shown below.
Part A
Note that y = f(x).
The x-intercepts identify values where the function or y=0. The x-intercepts occur at x=0 and x=20, or at (0,0) and (20,0).
The maximum value of y occurs at the vertex (10, 15) because the curve is down due to the negative leading coefficient of -0.15.
The curve increases in the interval x = (-∞, 10) and it decreases in the interval x = (10, ∞).
Part B
When x=12, y = -0.15(12 - 10)² + 15 = 14.4When x=15, y = -0.15(15 - 10)² + 15 = 11.25
The average rate of change between x =12 to x = 15 is(11.25 - 14.4)/(15 - 12) = -1.05
This rate of change represents the slope of the secant line from A to B. It approximates the rate at which f(x) decreases in the interval x =[12, 15].
Answer:
The correct answer AC = 11.52
Step-by-step explanation:
From the figure attached with this answer shows the triangle ABC.
BC=4 centimeters, m angle B=m angle c, and m angle a = 20 degrees
To find AC
From the figure we can see that D is the mid point and AD⊥BC
Then BD = CD = 4/2 = 2 cm
<BAD = 10° and <CAD = 10°
By using trigonometric ratio,
sin 10 = CD/AC = 2/AC
AC = 2/sin 10 = 2/0.1736 = 11.52
Therefore the value of AC = 11.52 cm
