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2 years ago

Help pls and thank u! ...

Mathematics

1 answer:

RUDIKE [14]2 years ago

3 0

Answer:

the first problem has infinite solutions, the second has one, and the third also has infinite solutions!

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If f(3) = 24, what is f-1 (24)?

True [87]

Answer:

f=25

Step-by-step explanation:

24+1=25

25-1=24

5 0

2 years ago

Sara tried to evaluate 21 : 7 x 8 step-by-step

nlexa [21]

Answer: Sara multiplied by 3 when she should have multiplied by 8.

Step-by-step explanation:

21 : 7*8

7*8 = 56

21 : 56

The simplest form of this ratio is 3 : 8

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3 years ago

An air conditioning technician charged Robert $77.25 to repair his air conditioning system after 3 hours of work. The technician

agasfer [191]

Answer:B

Step-by-step explanation:

He charged the man $25.75 for each hour and he worked for 3 hours so multiply $25.75 x 3 = $77.25

5 0

2 years ago

What is the image of ( − 5 , 4 ) (−5,4) after a reflection over the line y = x y=x?

balandron [24]

Answer:

(4,−5)

Step-by-step explanation:

7 0

2 years ago

5cosx -2sin(x/2) +7=0<br>Help me to find x step by step<br>pls

miskamm [114]

Answer:

x = 180

Step-by-step explanation:

First, you need to know

1. Double-angle formula:

cos(2x) = $cos^{2}x - sin^{2}x$

2. Pythagorean identity:

$cos^{2}x + sin^{2}x = 1$

Back to your problem, replacing the variable by the above:

$5cosx-sin\frac{x}{2}+7 = 0$

$5(cos^{2}\frac{x}{2}-sin^{2}\frac{x}{2}) - 2sin\frac{x}{2} + 7 = 0$ By Double-angle formula

$5(1 - 2sin^{2}\frac{x}{2}) - 2sin\frac{x}{2} + 7 = 0$ By Pythagorean identity

Given $y = \frac{x}{2}$

$5(1-2sin^{2}y) - 2siny + 7 = 0$

$10sin^{2}y+2siny-12=0$

$5sin^{2}y+siny-6=0$

$(5siny + 6)(siny - 1)=0$ , we know -1 < sinx < 1, for every x ∈ R

$siny = 1, y =90$

$y = \frac{x}{2}$

$x = 180$

8 0

3 years ago