Answer:
Step-by-step explanation:
The first parabola has vertex (-1, 0) and y-intercept (0, 1).
We plug these values into the given vertex form equation of a parabola:
y - k = a(x - h)^2 becomes
y - 0 = a(x + 1)^2
Next, we subst. the coordinates of the y-intercept (0, 1) into the above, obtaining:
1 = a(0 + 1)^2, and from this we know that a = 1. Thus, the equation of the first parabola is
y = (x + 1)^2
Second parabola: We follow essentially the same approach. Identify the vertex and the two horizontal intercepts. They are:
vertex: (1, 4)
x-intercepts: (-1, 0) and (3, 0)
Subbing these values into y - k = a(x - h)^2, we obtain:
0 - 4 = a(3 - 1)^2, or
-4 = a(2)². This yields a = -1.
Then the desired equation of the parabola is
y - 4 = -(x - 1)^2
Answer:
12x -y = -87
Step-by-step explanation:
You can start with the 2-point form of the equation of a line and manipulate it to give you the standard form.
y = (y2 -y1)/(x2 -x1)(x -x1) +y1
y = (-9 -3)/(-8 -(-7))(x -(-7)) +3
y = (-12/-1)(x +7) +3
y = 12x +84 +3
-12x +y = 87 . . . . . subtract the x-term
12x -y = -87 . . . . . . make the leading coefficient positive (per standard form)
Answer: There are 20 used bikes
Explanation: If there are 4 times the used bikes then you would have to do 80 divided by 4 and there’s the answer
Answer:
y(3y - 4)
Step-by-step explanation:

Both have y.
Factor y out of 
