Can someone tell me if this is correct or not my grades are bad

Elan Coil [88]

Answer:

En matemáticas, el volumen se puede definir como el espacio tridimensional encerrado por un límite u ocupado por un objeto. Aquí, los bloques y los libros ocupan espacio. ... El volumen de un objeto se mide en unidades cúbicas como centímetros cúbicos, pulgada cúbica, pie cúbico, metro cúbico.

Step-by-step explanation:

espero que esto ayude.

7 0

2 years ago

Find the missing sides.

love history [14]

Answer:

Part 3)

$x=6\ units$

$y=3\ units$

Part 4) $x=18\sqrt{2}\ units$

Step-by-step explanation:

Part 3)

Find the value of x

In the right triangle of the figure we know that

The cosine of angle of 30 degrees is equal to the adjacent side to angle of 30 degrees divide by the hypotenuse

so

$cos(30\°)=\frac{3\sqrt{3}}{x}$

and remember that

$cos(30\°)=\frac{\sqrt{3}}{2}$

substitute

$\frac{\sqrt{3}}{2}=\frac{3\sqrt{3}}{x}$

Simplify

$x=(2*3)=6\ units$

Find the value of y

In the right triangle of the figure we know that

The sine of angle of 30 degrees is equal to the opposite side to angle of 30 degrees divide by the hypotenuse

so

$sin(30\°)=\frac{y}{x}$

and remember that

$sin(30\°)=\frac{1}{2}$

substitute

$\frac{1}{2}=\frac{y}{6}$

$y=6/2=3\ units$

Part 4) Find the value of x

Applying the Pythagoras Theorem

$x^{2} =18^{2} +18^{2} \\ \\x^{2} = 324+324\\ \\x^{2}=648\\ \\x=\sqrt{648}\ units$

Simplify

$x=18\sqrt{2}\ units$

6 0

2 years ago

HELP...Cant figure it out

ziro4ka [17]

Answer:44

Step-by-step explanation:

-8(-6) -4

48 -4

44

4 0

3 years ago

2.The number of grams A of a certain radioactive substance present at time, in yearsfrom the present, t is given by the formulaA

professor190 [17]

Answer:

Given that,

The number of grams A of a certain radioactive substance present at time, in years

from the present, t is given by the formula

$A=45e^{-0.0045(t)}$

a) To find the initial amount of this substance

At t=0, we get

$A=45e^{-0.0045(0)}$ $A=45e^0$

We know that e^0=1 ( anything to the power zero is 1)

we get,

$A=45$

The initial amount of the substance is 45 grams

b)To find thehalf-life of this substance

To find t when the substance becames half the amount.

A=45/2

Substitute this we get,

$\frac{45}{2}=45e^{-0.0045(t)}$

$\frac{1}{2}=e^{-0.0045(t)}$

Taking natural logarithm on both sides we get,

$\ln (\frac{1}{2})=-0.0045(t)^{}$ $(-1)\ln (\frac{1}{2})=0.0045(t)$ $\ln (\frac{1}{2})^{-1}=0.0045(t)$ $\ln (2)=0.0045(t)$ $0.6931=0.0045(t)$ $t=\frac{0.6931}{0.0045}$ $t=154.02$

Half-life of this substance is 154.02

c) To find the amount of substance will be present around in 2500 years

Put t=2500

we get,