The answer is z=-b/c-c/4+1/4
<u><em>Answer:</em></u>
y^2 = 28x
<em><u>Step-by-step explanation:</u></em>
Since the directrix is horizontal, use the equation of a parabola that opens left or right.
(y−k)^2 = 4p(x−h)
Find the vertex.
(0,0)
Find the distance from the focus to the vertex.
p = 7
Substitute in the known values for the variables into the equation
(y−k)^2 = 4p(x−h).
(y−0)^2 = 4(7)(x−0)
Simplify.
<em>y^2 = 28x</em>
B. (6, -8)
First, you need to figure out the slope of the line
(y1 - y2) / (x1 - x2)
After substituting points D(-3, 4) A(3, -4)
[4 - (-4)] / (-3 - 3)
(8) / (-6)
The slope of the line is -8/6 or -4/3 simplified
Then you can put it in point slope form:
(y - y1) = m(x - x1)
(y - y1) = -4/3(x - x1)
The point that I am using for point slope form is A(3, -4)
[y - (-4)] = -4/3(x - 3)
y + 4 = -4/3(x - 3)
Next you have to simplify the equation so that y is isolated
y + 4 = -4/3(x - 3)
First distribute the -4/3
y + 4 = -4/3(x) + (-4/3)(-3)
y + 4 = -4/3x + 4
Subtract 4 on both sides
y + 4 - 4 = -4/3x + 4 - 4
y = -4/3x
Now that you have y = -4/3x, you can substitute the values until one of them makes the equation equal
For example) (6, -8)
-8 = -4/3(6)
-8 = -8
So since (6, -8) fits in the slope intercept equation, it must me collinear with points A and D
~~hope this helps~~
If x is length of the diagonal then
x^2 = 3^2 + 4^2 = 25
x = sqrt25 = 5
Diagonal is 5 units long
