Answer: (-1, 4) is the vertex of the parabola.
To find the vertex when you are given the equation in vertex form, all you have to do is look at the letters k and h. They will tell you what the vertex is.
It is always (h, k)
There is only one trick in this problem. You have to change "(x + 1)" to "(x - (-1))" since the format of the equation requires "(x - h)".
This makes the h value -1 instead of 1.
For number one
S: supplement.
R: angle1+angle8 =18
#2
S: supplement
R: angle 3+ angle 6=180
The equation x=2t-1 represent the x-coordinate. To get the value of x, substitute t with -1.
That is: x = 2(-1) - 1
= -2-1
= -3
Likewise, the equation y=t∧-3 represent the y-coordinate. Substituting t with -1,
y = (-1)∧-3
= -1
The point that correspond to t=-1 is (-3,-1).
Let the speed for the first 12 mi be x mi/h, the speed for 18 mi was (x+4) mi/h
thus given that
time=distance/speed
the average time will be:
3=(12+18)/(x+x+4)
3=30/(2x+4)
solving for x we get
3(2x+4)=30
6x+6=30
6x=24
x=4 mi/hr
Answer: 12 mi/hr
