Jane cycled 32km, correct to the nearest km.

two bags each contain blue marbles and black marbles. the first contains 4 blue marbles and 6 black marbles and the second bag c

amid [387]

There are two bags: a bag with 4 blue marbles and 6 black marbles and another one containing 6 blue marbles and <span>6 black marbles. the probability of getting a blue marble in the first bag is 6/10 or 3/5 while that on the second bag is 6/12 or 1/2. Hence the total probability of getting two marbles is c. 3/10. </span>

4 0

2 years ago

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

2 years ago

Simplify -3p 3 + 5p + (-2p 2) + (-4) - 12p + 5 - (-8p 3).

MissTica

Answer:5p^3-2p^2-7p+1

Step-by-step explanation:

-3p^3+5p+(-2p^2)+(-4)-12p+5-(-8p^3)

open brackets

-3p^3+5p-2p^2-4-12p+5+8p^3

Collect like terms

-3p^3+8p^3-2p^2+5p-12p-4+5

5p^3-2p^2-7p+1

3 0

3 years ago

HURRRRRRYYYYYYY 1 QUESTION EXPERTS/ACE HELP QUICK!!!!!

Tomtit [17]

I believe the answer is 275 miles. Hope this helps!

8 0

3 years ago

Read 2 more answers

Please help me, I know it’s not the first one but I think it’s the last one. Can somebody please confirm or deny?

GaryK [48]

Answer:

B. 2.2π m² : 3.2π m²

Step-by-step explanation:

Given:

Slant height (l) = 2.2 m

Diameter (d) = 2 m

Radius (r) = ½(2) = 1 m

Required:

Lateral area and surface area

Solution:

✔️Formula for lateral area of a cone = πrl

Plug in the values

Lateral area of the cone = π*1*2.2

Lateral area = 2.2π m²

✔️ Formula for surface area of a cone = πr(l + r)

Plug in the values

Surface area of the cone = π*1(2.2 + 1)

Surface area = π(3.2)

Surface area = 3.2π m²

The answer would therefore be:

2.2π m² : 3.2π m²

7 0

2 years ago