The boundary of the lawn in front of a building is represented by the parabola
y = (x^2) /16 + x - 2
And you have three questions which require to find the focus, the vertex and the directrix of the parabola.
Note that it is a regular parabola (its symmetry axis is paralell to the y-axis).
1) Focus:
It is a point on the symmetry axis => x = the x-component of the vertex) at a distance equal to the distance between the directrix and the vertex).
In a regular parabola, the y - coordinate of the focus is p units from the y-coordinate of the focus, and p is equal to 1/(4a), where a is the coefficient that appears in this form of the parabola's equation: y = a(x - h)^2 + k (this is called the vertex form)
Then we will rearrange the standard form, (x^2)/16 + x - 2 fo find the vertex form y = a(x-h)^2 + k
What we need is to complete a square. You can follow these steps.
1) Extract common factor 1/16 => (1/16) [ (x^2) + 16x - 32]
2) Add (and subtract) the square of the half value of the coefficent ot the term on x =>
16/2 = 8 => add and subtract 8^2 => (1/16) [ (x^2) + 16 x + 8^2 - 32 - 8^2]
3) The three first terms inside the square brackets are a perfect square trinomial: =>
(1/16) [ (x+8)^2 - 32 - 64] = (1/16) [ (x+8)^2 - 96] =>
(1/16) [(x+8)^2 ] - 96/16 =>
(1/16) (x +8)^2 - 6
Which is now in the form a(x - h)^2 + k, where:
a = 1/16 , h = - 8, and k = -6
(h,k) is the vertex: h is the x-coordinate of the vertex, and k is the y-coordinate of the vertex.
=> a = 1/16 => p =1/4a = 16/4 = 4
y-componente of the focus = -6 + 4 = -2
x-component of the focus = h = - 8
=> focus = (-8, -2)
2) Vertex
We found it above, vertex = (h,k) = (-8,-6)
3) Directrix
It is the line y = p units below the vertex = > y = -6 - 4 = -10
y = -10
Answer:
B
Step-by-step explanation:
Substitute the x value into the right side of the function and if the value obtained is equal to the y value of the point then it is a solution.
(0, - 4) → y = 5(0) - 4 = 0 - 4 = -4 ← True
(2, 6) → y = 5(2) - 4 = 10 - 4 = 6 ← True
(4, 20) → 5(4) - 4 = 20 - 4 = 16 ← False
(4, 16) → 5(4) - 4 = 20 - 4 = 16 ← True
(0, - 4), (2, 6), (4, 16) ← possible inputs and outputs
A boat has a ladder that has six rungs. Each rung is one foot apart. The bottom rung is one foot from the water. The tide rises at 12 inches every 15 minutes
Answer:
X < -9
Step-by-step explanation:
5a +18 < -27
5a < -27 -18
5a < - 45
5a/5 < - 45/5
a < - 9
Answred by Gauthmath
Volume is a three-dimensional scalar quantity. The volume of the water that Marry should pour into the vase is 241.28 cubic inches.
<h3>What is volume?</h3>
A volume is a scalar number that expresses the amount of three-dimensional space enclosed by a closed surface.
Given the radius of the flower vase is 4 inches, while the height of the vase is 6 inches, therefore, the total volume of the vase is,
Volume = πR²×H = π× 4²×6 = 301.6 in³
Since the volume of the vase is 301.6 in³, but the store has told her to fill the vase 4/5 of its capacity, therefore, the volume of water Marry should pour is,
Volume of water = (4/5) × 301.6 in³ = 241.28 cubic inches
Hence, the volume of the water that Marry should pour into the vase is 241.28 cubic inches.
Learn more about Volume:
brainly.com/question/13338592
#SPJ1