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:
D. y=4x
Step-by-step explanation:
It asks for a proportional relationship between x and y
And is the only answer
because
When x and y is 1 the answer is
4/1
And when x and y is 2 the answer is
8/2
If you divide both of them are still 4
And this will always be the result no matter how many times you do it
like if you put it as 150
150 times 4 is 600/150
600 divided by 150 is 4
Hope this helps!
Answer: Do you know what the total degree is but if not an algebraic equation us 148-x = 26
Step-by-step explanation:
Answer:
the answer is d. 4x²+x-6
Step-by-step explanation:
In order to combine the fractions, they need to have the same denominator.
So, multiply each of their numerators by the denominator they need to be equivalent.
This would look like this:
3x/x+3 --> 3x(x)/x(x+3) ---simplify this as--> 3x²/x(x+3)
x-2/x --> (x-2)(x+3)/x(x+3) ---simplify this as --> x²+x - 6/x(x+3)
3x 3x(x) x-2 (x-2)(x+3)
----- ---> ----- and -------- ---> ---------
x+3 x(x+3) x x(x+3)
now that both fractions have the same denominator, we can add their numerators.
3x² + x²+x-6 = 4x²+x -6
This should now look like this:
4x²+x -6
-------------
x(x+3)
