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2 years ago

Which expressions are equivalent to the one below ? check all that apply :)

Mathematics

2 answers:

lys-0071 [83]2 years ago

8 0

Answer:

its b and e

Step-by-step explanation:

Stella [2.4K]2 years ago

5 0

Answer:

Option D and E are equivalent to the given expression.

Step-by-step explanation:

Given : $\frac{21^x}{3^x}$

Solution:

$\frac{21^x}{3^x}$

Using identity : $\frac{a^x}{b^x} = (\frac{a}{b})^x$

$(\frac{21}{3})^x$ -- Option E

Now this can be written as $21^x = 7^x \times 3^x$

Identity : $a^x \times b^x = (a \cdot b)^x$

$\frac{7^x \times 3^x}{3^x}$ -- Option D

$(7)^x$ -- Option D

Thus Option D and E are equivalent to the given expression.

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I need help with this

yawa3891 [41]

Answer:

Step-by-step explanation:

In the graph given, we can expect the x axis to be horizontal and the y axis to be vertical. This means that the arm span represents y and the height represents x.

Therefore, if a girl on her team is 63 inches tall, we can say that y=x+2, and since height is x, y = 63 + 2 = 65

6 0

2 years ago

Plz help<br> and explain

vovikov84 [41]

To solve this problem, we need to first find the dimensions of the side of the blue and purple squares.

We're given that the purple (smaller) square has a side length of x inches.
We are also given that the blue band has a width of 5 inches.
Since the blue band surrounds the purple square on both sides, the length of the blue square is x+2(5)=x+10 inches.

The net area of the band is therefore the difference of the area of the blue square and the purple square, namely take out the area of the purple square from the blue.

Therefore
Area of band
$=(x+10)^2-x^2$ [recall $(a+b)^2=a^2+2ab+b^2$
$=x^2+20x+100-x^2$
$=20x+100$ or 20(x+5) if you wish.

8 0

3 years ago

What is the value of x?<br> Enter your answer in the box

Gre4nikov [31]

The horizontal value in a pair of coordinates: how far along the point is. The X Coordinate is always written first in an ordered pair of coordinates (x,y), such as (12,5). In this example, the value "12" is the X Coordinate. Also called "Abscissa" See: Coordinates.

5 0

2 years ago

A pilot traveling 175 miles per hour encounters a head wind of 35 knots. If there are 1.15 knots per mph, what will her true spe

KonstantinChe [14]

Since one knot is 1.15 mph.
We multiply 35 time 1.15, which equals 40.25 mph.
Then we subtract. 175 - 4.25 = 134.75
Round, and you'll get 135mph
Therefore, your answer is 135mph

3 0

3 years ago

A cube has a surface area of 486 cm2. What is the side length ?

astraxan [27]

A Cube, has all equal sides, namely, the length, width and height
are all equal to each other

so.. notice the picture added here
you have really, 6 squares, stacked up to each other at the edges

so...what is the Area of one of those squares?
well, if the sides are equal, let's say the side is "x" long, then
the Area is $x\cdot x \implies x^2$

well, you have 6 of those squares, thus $\bf \textit{surface area of a cube}=
\begin{cases}
(x\cdot x)+\\
(x\cdot x)+\\
(x\cdot x)+\\
(x\cdot x)+\\
(x\cdot x)+\\
(x\cdot x)\\
 --------------\\
 x^2+x^2+x^2+x^2+x^2\\
6x^2
\end{cases}
\\\\
\textit{we know the Area is }486\ cm^2\qquad thus
\\\\
\textit{surface area}=6x^2\implies 486=6x^2$

solve for "x", to get one side's length

3 0

3 years ago