Answer:
Step-by-step explanation:
Since the vertex is right between the vertex and the directrix, the y value of the vertex must be (3+(-1))/2=1. The x coordinate will just be the same as that of the focus, or in this case 0. This means that the vertex will be at (0,1). Since the graph opens toward the focus, it will be opening up, and since its vertex is at (0,1), it will have an equation of:
Hope this helps!
Answer:
Hi There the correct answer is {x,y} = {-1,-10}
System of Linear Equations entered :
[1] 3x - y = 7
[2] 4x - 2y = 16
Graphic Representation of the Equations :
y + 3x = 7 -2y + 4x = 16
Solve by Substitution :
// Solve equation [1] for the variable y
[1] y = 3x - 7
// Plug this in for variable y in equation [2]
[2] 4x - 2•(3x-7) = 16
[2] -2x = 2
// Solve equation [2] for the variable x
[2] 2x = - 2
[2] x = - 1
// By now we know this much :
x = -1
y = 3x-7
// Use the x value to solve for y
y = 3(-1)-7 = -10
Solution :
{x,y} = {-1,-10}
Hope it helps!
Answer:
16. B
17. B
Step-by-step explanation:
16. The intercept form of the parabola is
where 
are two x-intercepts.
In your case,
so
To find <em>a</em>, substitute coordinates of the point (-6,-4) parabola is passing through
and
17. The vertex form of the parabola equation is
where <em>(h,k)</em> are the coordinates of the vertex and sign "-" because parabola goes down.
In your case, vertex is (2,3), so
The vertex is 3 units from the focus, then
The equation of the parabola is
Answer:
B. 16 hrs
Step-by-step explanation:
Distance = rate × time
The best way to do this is to make a table with the info. We are concerned with the trip There and the Return trip. Set it up accordingly:
d = r × t
There
Return
The train made a trip from A to B and then back to A again, so the distances are both the same. We don't know what the distance is, but it doesn't matter. Just go with it for now. It'll be important later.
d = r × t
There d
Return d
We are also told the rates. There is 70 km/hr and return is 80 km/hr
d = r × t
There d = 70
Return d = 80
All that's left is the time column now. We don't know how long it took to get there or back, but if it took 2 hours longer to get There than on the Return, the Return trip took t and the There trip took t + 2:
d = r × t
There d = 70 × t+2
Return d = 80 × t
The distances, remember, are the same for both trips, so that means that by the transitive property of equality, their equations can be set equal to each other:
70(t + 2) = 80t
70t + 140 = 80t
140 = 10t
14 = t
That t represents the Return trip's time. Add 2 hours to it since the There trip's time is t+2. So 14 + 2 = 16.
B. 16 hours
Answer:
I am not sure but for me the answer is 1
