The directrix x=-7 must be perpendicular to the axis that goes through the focus (7,0), then the axis of this parabola is y=0
The directrix cuts the axis of the parabola at the point (-7,0)
The vertex of the parabola V=(h,k) is the midpoint of the points (-7,0) and (7,0=
h=(-7+7)/2=(0)/2→h=0
k=(0+0)/2=(0)/2→k=0
Vertex: V=(h,k)→V=(0,0)
As the axis of the parabola is horizontal, the parabola has an equation of the form:
(y-k)^2=4p(x-h)
The parabola opens to the right then p is positive (p>0)
p is the distance between the vertex and the focus, the p=7
(y-k)^2=4p(x-h)
(y-0)^2=4(7)(x-0)
y^2=28x
Answer: <span>The equation of the parabola whose focus is at (7, 0) and directrix at x = -7 is: y^2=28x</span>
We know that
if <span>y varies inversely as x----------> the equation is y=k/x
where
k--------> </span><span> is the constant of variation</span><span>
for x=3.3 y=15
then
y=k/x--------> 15=k/3.3---------> k=15*3.3--------> k=49.5
so
y=49.5/x
the answer is
y=49.5/x</span>
-3x-2(5x-7)=-12
-3x-10x+14=-12
-12-14=-26
-3x-10x= -13x
So -13x=-26
x= 2
The area of the polygon with the given vertices: (-3,3) (-3,-1) (4,-1) (4,3) is 28 square units
<h3>What is rectangle ?</h3>
A rectangle is a polygon with four sides. The opposite sides of a rectangle are equal while the angles at the vertex is orthogonal
<h3>How to solve for area of the rectangle</h3>
The following are the data given in the question
polygon with the given vertices' as:
(-3,3)
(-3,-1)
(4,-1)
(4,3)
plotting the given polygon shows it is a rectangle with sides
Length, L = 7 units
Width, w = 4 units
Area if a rectangle is given by
= L * w
= 7 * 4
= 28 square units
The area of the polygon is 28 square units
Learn more in area of rectangle: brainly.com/question/16239445
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