Step-by-step explanation:
If the parabola has the form
(vertex form)
then its vertex is located at the point (h, k). Therefore, the vertex of the parabola
is located at the point (8, 6).
To find the length of the parabola's latus rectum, we need to find its focal length <em>f</em>. Luckily, since our equation is in vertex form, we can easily find from the focus (or focal point) coordinate, which is
where 
is called the focal length or distance of the focus from the vertex. So from our equation, we can see that the focal length <em>f</em> is
By definition, the length of the latus rectum is four times the focal length so therefore, its value is
X/2 >= -4
x >= -4 * 2
x >= -8
Answer:
Original Price= $20
Sales Price= $20*0.80= $16
Answer:
width= 75 cm
Step-by-step explanation:
We need to recall the formula to calculate the area of a rectangle, since we are dealing with a rectangular window:
Area of rectangle = width * length
therefore, since they give us the window's area: 6525 
, and also the window's length: 87 cm, we just need to replace those values in the area formula and solve for the unknown "width". We do such by dividing both sides of the equation by 87 cm in order to isolate the unknown on one side of the equal sign;
