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2 years ago

Which choice is equivalent to the expression √20 + √80

Mathematics

2 answers:

salantis [7]2 years ago

7 0

Answer:

13.41

Step-by-step explanation:

Hope it helps!

Korvikt [17]2 years ago

5 0

Answer:

6 $\sqrt{5}$

Step-by-step explanation:

Using the rule of radicals

$\sqrt{a}$ × $\sqrt{b}$ ⇔ $\sqrt{ab}$

Simplifying the radicals

$\sqrt{20}$

= $\sqrt{4(5)}$

= $\sqrt{4}$ × $\sqrt{5}$ = 2 $\sqrt{5}$

$\sqrt{80}$

= $\sqrt{16(5)}$

= $\sqrt{16}$ × $\sqrt{5}$ = 4 $\sqrt{5}$

Then

$\sqrt{20}$ + $\sqrt{80}$

= 2 $\sqrt{5}$ + 4 $\sqrt{5}$

= 6 $\sqrt{5}$

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6x-3-11-8x=2 please show work

Ludmilka [50]

Answer: is x = -8

this is how i got it ______

6 x - 3 - 11 - 8 x = 2

(simplify both sides and combine like terms)

(6x + -8x ) + ( -3 + -11) = 2

- 2x + -14 = 2

-2x - 14 = 2

( then you add 14 to both sides)

- 2x - 14 = 2

+14 +14

-2x = 16

( then you divide both sides by -2)

-2x / -2 = 16/ -2

x = -8

ta da!! happy to help!

it made it here. this is for the second one.

( first, we subtract 8n from both sides)

13n + 26 = 8n - 29

-8n -8n

5n + 26 = -29

( then we subtract 26 from both sides)

5n + 26 = -29

- 26 -26

5n = - 55

(after that we divide both sides by 5, we do this to make n alone )

5n/ 5 = -55/ 5

n = -11

7 0

2 years ago

If u(x)=-2x²+3 and v(x)=1/x, what is the range of (u ° v)(x)?

Ludmilka [50]

$u(x)=-2x^2+3\\\\v(x)=\dfrac{1}{x}\\\\(u\ \circ\ v)(x)=-2\left(\dfrac{1}{x}\right)^2+3=-2\left(\dfrac{1}{x^2}\right)+3=-\dfrac{1}{x^2}+3\\\\\text{The range of}\ y=\dfrac{1}{x^2}\ \text{is all positive real numbers.}\\\\\text{The range of}\ y=-\dfrac{1}{x^2}\ \text{is all negative real numbers.}\\\\\text{The range of }\ (u\ \circ\ v)(x)=-\dfrac{1}{x^2}+3\ is\ (-\infty,\ 3)$