Which of the following rules represents the set of ordered pairs?

A jumping spider's movement is modeled by a parabola. The spider makes a single jump from the origin and reaches a maximum heigh

Stella [2.4K]

A parabola is a mirror-symmetrical U-shape.

The equation of the parabola is $\mathbf{y = -\frac{1}{640}(x - 80)^2 + 10}$
The focus is $\mathbf{Focus = (80, -1760)}$
The directrix is $\mathbf{y = \frac{1}{640}}$
The axis of the symmetry of parabola is: $\mathbf{x = 80}$

From the question, we have:

$\mathbf{Vertex: (h,k) = (80,10)}$

$\mathbf{Origin: (x,y) = (0,0)}$

The equation of a parabola is:

$\mathbf{y = a(x - h)^2 + k}$

Substitute the values of origin and vertex in $\mathbf{y = a(x - h)^2 + k}$

$\mathbf{0 = a(0 - 80)^2 + 10}$

$\mathbf{0 = a(- 80)^2 + 10}$

$\mathbf{0 = 6400a + 10}$

Collect like terms

$\mathbf{6400a =- 10}$

Solve for a

$\mathbf{a =- \frac{1}{640}}$

Substitute the values of a and the vertex in $\mathbf{y = a(x - h)^2 + k}$

$\mathbf{y = -\frac{1}{640}(x - 80)^2 + 10}$

The focus of a parabola is:

$\mathbf{Focus = (h, \frac{k+1}{4a})}$

Substitute the values of a and the vertex in $\mathbf{Focus = (h, \frac{k+1}{4a})}$

$\mathbf{Focus = (80, \frac{10+1}{4 \times -\frac{1}{640}})}$

$\mathbf{Focus = (80, -\frac{11}{\frac{1}{160}})}$

$\mathbf{Focus = (80, -11\times 160)}$

$\mathbf{Focus = (80, -1760)}$

The equation of the directrix is:

$\mathbf{y = -a}$

So, we have:

$\mathbf{y = \frac{1}{640}}$ ----- the directrix

The axis of symmetry is:

$\mathbf{x = -\frac{b}{2a}}$

We have:

$\mathbf{y = -\frac{1}{640}(x - 80)^2 + 10}$

Expand

$\mathbf{y = -\frac{1}{640}(x^2 -160x + 6400) +10}$

Expand

$\mathbf{y = -\frac{1}{640}x^2 +\frac{1}{4}x - 10 +10}$

$\mathbf{y = -\frac{1}{640}x^2 +\frac{1}{4}x }$

A quadratic function is represented as:

$\mathbf{y = ax^2 + bx + c}$

So, we have:

$\mathbf{a = -\frac{1}{640}}$

$\mathbf{b = \frac{1}{4}}$

Recall that:

$\mathbf{x = -\frac{b}{2a}}$

So, we have:

$\mathbf{x = -\frac{1/4}{2 \times -1/640}}$

$\mathbf{x = \frac{1/4}{1/320}}$

This gives

$\mathbf{x = \frac{320}{4}}$

$\mathbf{x = 80}$

Hence, the axis of the symmetry of parabola is: $\mathbf{x = 80}$

Read more about parabola at:

brainly.com/question/21685473

6 0

3 years ago

a restaurant offers a lunch special in which a customer can select from one of the 7 appetizers, one of the 10 entrees, and one

Amiraneli [1.4K]

Answer:

420

Step-by-step explanation:

Each of the 7 appetizers can be paired with one of 10 entrees, and each entree can be paired with one of 6 desserts. So the number of combinations is:

7 × 10 × 6 = 420

6 0

3 years ago

For each triangle, check all that apply

Alex Ar [27]

Triangle A is an Isosceles

Triangle B is Equilateral

Triangle C is Scalene

7 0

4 years ago

Read 3 more answers

Year 9 Maths - linear equations please help

jek_recluse [69]

Answer:

x=1 & y=6 or (1,6)

Step-by-step explanation:

3x-x+5=7 Substitute the 2nd equation in for y

2x+5=7 Do 3x-x to get 2x

2x=2 Subtract 5 from both sides

x=1 Divide 2 from both sides

y=1+5 Insert 1 as x

y=6 Add 1+5 to solve for y

Hope this helped!

3 0

3 years ago

Read 2 more answers

Ahmed bought a car for $5000 which is the 80% of the original price of the car. Calculate the original price of the car.

WITCHER [35]

Answer:

$6250

Step-by-step explanation:

5000 = 80%

5000/80=62.5

62.5*100=6250

8 0

3 years ago

Read 2 more answers