All categories

3 years ago

What is the value of x in the equaton

itle=" {25}x^{2} = 16" alt=" {25}x^{2} = 16" align="absmiddle" class="latex-formula">

Mathematics

1 answer:

lisov135 [29]3 years ago

5 0

$25x^2=16\ \ \ |:25\\\\x^2=\dfrac{16}{25}\to x=\pm\sqrt{\dfrac{16}{25}}\\\\x=-\dfrac{\sqrt{16}}{\sqrt{25}}\ \vee\ x=\dfrac{\sqrt{16}}{\sqrt{25}}\\\\\boxed{x=-\dfrac{4}{5}\ \vee\ x=\dfrac{4}{5}}$

You might be interested in

A cylindrical can without a top is made to contain 25 3 cm of liquid. What are the dimensions of the can that will minimize the

Basile [38]

Answer:

Therefore the radius of the can is 1.71 cm and height of the can is 2.72 cm.

Step-by-step explanation:

Given that, the volume of cylindrical can with out top is 25 cm³.

Consider the height of the can be h and radius be r.

The volume of the can is V= $\pi r^2h$

According to the problem,

$\pi r^2 h=25$

$\Rightarrow h=\frac{25}{\pi r^2}$

The surface area of the base of the can is = $\pi r^2$

The metal for the bottom will cost $2.00 per cm²

The metal cost for the base is =$(2.00× $\pi r^2$ )

The lateral surface area of the can is = $2\pi rh$

The metal for the side will cost $1.25 per cm²

The metal cost for the base is =$(1.25× $2\pi rh$ )

$=\$2.5 \pi r h$

Total cost of metal is C= 2.00 $\pi r^2$ + $2.5 \pi r h$

Putting $h=\frac{25}{\pi r^2}$

$\therefore C=2\pi r^2+2.5 \pi r \times \frac{25}{\pi r^2}$

$\Rightarrow C=2\pi r^2+ \frac{62.5}{ r}$

Differentiating with respect to r

$C'=4\pi r- \frac{62.5}{ r^2}$

Again differentiating with respect to r

$C''=4\pi + \frac{125}{ r^3}$

To find the minimize cost, we set C'=0

$4\pi r- \frac{62.5}{ r^2}=0$

$\Rightarrow 4\pi r=\frac{62.5}{ r^2}$

$\Rightarrow r^3=\frac{62.5}{ 4\pi}$

⇒r=1.71

Now,

$\left C''\right|_{x=1.71}=4\pi +\frac{125}{1.71^3}>0$

When r=1.71 cm, the metal cost will be minimum.

Therefore,

$h=\frac{25}{\pi\times 1.71^2}$

⇒h=2.72 cm

Therefore the radius of the can is 1.71 cm and height of the can is 2.72 cm.

6 0

3 years ago

Demarco has 2.25 worth of nickels in his piggy prank. how many total nickels does he have

lidiya [134]

Answer:45 nickels

Step-by-step explanation:

If a nickel is $ 0.05 , than $ 2.25 divided by. $0.05 is 45.

3 0

3 years ago

Combine like terms.<br> 2y2 – 5+1 + 2y2 – 6y2 – 3 – 4y<br> ASAP<br> someone help please

AnnZ [28]

Answer:

-2y2 - 4y - 7

Step-by-step explanation:

2y2 + 2y2 - 6y2 - 4y - 5 - 3 + 1

4y2 - 6y2 - 4y - 8 + 1

-2y2 - 4y - 7

3 0

3 years ago

Read 2 more answers

CAN SOMEONE HELP WITH THIS??????????????

svetoff [14.1K]

Answer:

8963.46

Step-by-step explanation:

84*66 for the rectangle and since there is two semi circles you could just calculate it as one so it would be 84*66+33*33*3.14 because formula for area of circle is A= pi*raduis with exponant of 2

3 0

3 years ago

Would you use grams or kilometers as the unit to measure the mass of a strawberry PLEASE ANSWER ALL YHE QUESTIONS!!! Get brainli

skelet666 [1.2K]

Answer:

You'd use grams because the strawberry is so small, and kilograms are emasuring bigger things.

Step-by-step explanation:

8 0

3 years ago

Read 2 more answers