All categories

2 years ago

Please help!!!!!! Solve for x:

Mathematics

1 answer:

nordsb [41]2 years ago

8 0

A
Explanation: You want to get x by itself. So add +7 to -7 to cancel it out, do the same thing to 4.
x-7=4
+7+7
x=11
x

You might be interested in

I need help with 9 12 15 13 and 10

Lera25 [3.4K]

10. x=2
12. x=-7
Thats all I have so far if you need more help email me [email protected]

8 0

3 years ago

Read 2 more answers

A waitress believes the distribution of her tips has a model that is slightly skewed to the left, with a mean of $8.30 and a s

kondaur [170]

Answer:

probability = 0.9286

Step-by-step explanation:

given data

mean = $8.30

standard deviation = $4.70

waits parties over a weekend of work = 60

solution

when we earn at least $550 in 60 parties

so average per party will be x = $\frac{550}{60}$

average x = 9.1667

so now we get here z value that is

$z = \frac{x-\mu }{\sigma }$ ...............1

put here value and we get

z = $\frac{9.1667-8.30}{4.70}$

z = 0.184404

P(x>9.1667) = P(z>0.184404)

use standard normal table

probability = 1 - 0.0714 = 0.9286

8 0

3 years ago

What is the ratio for 0.34%?

Shalnov [3]

Answer:

0.34 is 34/100

The ratio is 34/100

5 0

4 years ago

Read 2 more answers

Please help me I really need someone's helppp

soldier1979 [14.2K]

Its an acute angle, im in 6th grade, and your in high school so..... im sorry if i get it wrong, but hey! i tried! lol

5 0

3 years ago

Read 2 more answers

Futhe Mathematics <img src="https://tex.z-dn.net/?f=%28Cos%20%7B%7D%5E%7B4%7Dt%20-Sin%20%7B%7D%5E%7B4%7Dt%20%29%20%20%5Cdiv%2

Nastasia [14]

Answer:

cos2t/cos²t

Step-by-step explanation:

Here the given trigonometric expression to us is ,

$\longrightarrow \dfrac{cos^4t - sin^4t }{cos^2t }$

We can write the numerator as ,

$\longrightarrow \dfrac{ (cos^2t)^2-(sin^2t)^2}{cos^2t }$

Recall the identity ,

$\longrightarrow (a-b)(a+b)=a^2-b^2$

Using this we have ,

$\longrightarrow \dfrac{(cos^2t + sin^2t)(cos^2t-sin^2t)}{cos^2t}$

Again , as we know that ,

$\longrightarrow sin^2\phi + cos^2\phi = 1$

Therefore we can rewrite it as ,

$\longrightarrow \dfrac{1(cos^2t - sin^2t)}{cos^2t}$

Again using the first identity mentioned above ,

$\longrightarrow \underline{\underline{\dfrac{(cost + sint )(cost - sint)}{cos^2t}}}$

Or else we can also write it using ,

$\longrightarrow cos2\phi = cos^2\phi - sin^2\phi$

Therefore ,

$\longrightarrow \underline{\underline{\dfrac{cos2t}{cos^2t}}}$

And we are done !

$\rule{200}{4}$

Additional info :-

Derivation of cos²x - sin²x = cos2x :-

We can rewrite cos 2x as ,

$\longrightarrow cos(x + x )$

As we know that ,

$\longrightarrow cos(y + z )= cosy.cosz - siny.sinz$

So that ,

$\longrightarrow cos(x+x) = cos(x).cos(x) - sin(x)sin(x)$

On simplifying,

$\longrightarrow cos(x+x) = cos^2x - sin^2x$

Hence,

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

$\rule{200}{4}$

7 0

3 years ago