<span>You are given a car moved at a constant velocity during the first hour. It stopped for 2 hours at a mall and then moved ahead again at a constant velocity for the next 3 hours. Then you are given the car that has finally returned to its starting point with a constant velocity in the next 2.5 hours. The graph that best represents the car's motion is First straight line joins ordered pairs 0, 0 and 1, 60, second straight line joins 1, 60 and 3, 60, third straight line joins 3, 60 and 6, 100 and fourth straight line joins 6, 100 and 8.5, 0.</span>
In a graph the roots of the function are given by the cut points with the x axis.
On the other hand, we have the following equation:
y = -x2 - x + 6
To find the roots, we equate to zero:
-x2 - x + 6 = 0
Rewriting we have:
x2 + x - 6 = 0
(x-2) (x + 3) = 0
The roots are:
x1 = 2
x2 = -3
Answer:
The roots are:
x1 = 2
x2 = -3
Y1 is the simplest parabola. Its vertex is at (0,0) and it passes thru (2,4). This is enough info to conclude that y1 = x^2.
y4, the lower red graph, is a bit more of a challenge. We can easily identify its vertex, which is (-4,0), and several points on the grah, such as (2,-3).
Let's try this: assume that the general equation for a parabola is
y-k = a(x-h)^2, where (h,k) is the vertex. Subst. the known values,
-3-(-4) = a(2-0)^2. Then 1 = a(2)^2, or 1 = 4a, or a = 1/4.
The equation of parabola y4 is y+4 = (1/4)x^2
Or you could elim. the fraction and write the eqn as 4y+16=x^2, or
4y = x^2-16, or y = (1/4)x - 4. Take your pick! Hope this helps you find "a" for the other parabolas.
27 time 8 equals 216
...
216 divided by 27 equals 8
