All categories

3 years ago

7. A racecar has a speed of 240 km/h. What is its speed in m/s?

Mathematics

1 answer:

uysha [10]3 years ago

6 0

Answer:

3.6.

Step-by-step explanation:

If i'm right can I get brainliest?

You might be interested in

(7,5), (r,9) m=6<br><br> What is r?

Igoryamba

Answer:

The answer is that r = 7/6

Step-by-step explanation:

Given point: (7, 5)

Given slope: m = 6

Use the point slope form of the equation:

y - y1 = m(x - x1)

y - 5 = 6(x - 7)

y - 5 = 6x - 7

y = 6x + 2

Now, find r for the point (r, 9) by substitution:

9 = 6x + 2

6x + 2 = 9

6x = 7

x = 7/6

Proof:

y = 6x + 2

f(x) = 6x + 2

f(7/6) = 6(7/6) + 2

= 42/6 + 2

= 7 + 2 = 9, giving (7/6, 9). r = 7/6

Hope this helps! Have a great day!

4 0

3 years ago

Can someone help me with this math

astra-53 [7]

Equal them to each other and you get that x=7

6 0

3 years ago

4x−2y=14 y=12x−1 solve by substitution

Tatiana [17]

Answer:

x= -3/5

Step-by-step explanation:

4x-2y=14

y=12x-1

4x-2(12x-1)=14

4x-24x+2=14

4x-24x=12

-20x=12

×= -12/20

x= -3/5

8 0

3 years ago

The two triangles are similar What is the value of x? Enter your answer in the box x =

lilavasa [31]

Answ x=59

Step-by-step explanation:

4 0

2 years ago

. A right cylindrical drum is to hold 7.35 cubic feet of liquid. Find the dimensions (radius of the base and height) of the drum

Drupady [299]

Answer:

$r=1.05\ \text{ft}$

$h=2.12\ \text{ft}$

$20.91\ \text{ft}^3$

Step-by-step explanation:

r = Radius

h = Height

Volume of cylinder = $7.35\ \text{ft}^3$

$V=\pi r^2h\\\Rightarrow h=\dfrac{V}{\pi r^2}\\\Rightarrow h=\dfrac{7.35}{\pi r^2}$

Surface area is given by

$A=2\pi r^2+2\pi rh\\\Rightarrow A=2\pi r^2+2\pi r\dfrac{7.35}{\pi r^2}\\\Rightarrow A=2\pi r^2+\dfrac{14.7}{r}$

Differentiating with respect to radius we get

$\dfrac{dA}{dr}=4\pi r-\dfrac{14.7}{r^2}$

Equating with zero we get

$0=4\pi r-\dfrac{14.7}{r^2}\\\Rightarrow 4\pi r=\dfrac{14.7}{r^2}\\\Rightarrow r^3=\dfrac{14.7}{4\pi}\\\Rightarrow r=(\dfrac{14.7}{4\pi})^{\dfrac{1}{3}}\\\Rightarrow r=1.05$

$\dfrac{d^2A}{dr^2}=4\pi-2\times \dfrac{14.7}{r^3}\\\Rightarrow \dfrac{d^2A}{dr^2}=4\pi+2\times \dfrac{14.7}{1.05^3}\\\Rightarrow \dfrac{d^2A}{dr^2}=37.96>0$

So, the value of the function is minimum at $r=1.05$

$h=\dfrac{7.35}{\pi r^2}=\dfrac{7.35}{\pi 1.05^2}\\\Rightarrow h=2.12$

So, the radius and height which would minimize the surface area is 1.05 feet and 2.12 feet respectively.

Surface area

$A=2\pi r^2+2\pi rh\\\Rightarrow A=2\pi \times 1.05^2+2\pi 1.05\times 2.12\\\Rightarrow A=20.91\ \text{ft}^3$

The minimum surface area is $20.91\ \text{ft}^3$ .

8 0

3 years ago