51 is 15% of what number?

Raul works for the city transportation department he made a table to show the number of people that can be transported on a diff

Andru [333]

Answer:

1 : 45

Step-by-step explanation:

225 divided by 5 equals 45. You can now use this ratio to determine the number of people with different amounts of buses; when you change x from 1 to n, you would need to multiply 45 by n, and you will have your new ratio column in the table.

Hope this helps :)

3 0

3 years ago

Read 2 more answers

Please help quick it’s a test

disa [49]

The rate must be in DECIMAL form and the time must be in YEARS

8 0

2 years ago

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

2 years ago

The sum of 12 and a number x is equal to 15

daser333 [38]

Answer:

The answer would be 3.

Step-by-step explanation:

This can be found by subtracting 12 from both sides and then the x will be alone on one side and be set equal to 3 on the other side.

4 0

2 years ago

Read 2 more answers

I only really need the domain and range, intervals, and end behavior. My Precalculus class never covered piecewise functions so

Serjik [45]

(a)

Domain:

we know that domain is all possible values of x for which any function ios defined

Here, curve is defined for all values of x

so, domain is

$(-\infty,\infty)$

Range:

Range is all possible values of y for which x is defined

minimum value of y is -4

maximium value of y is +inf

so, range is

$[-4,\infty)$

(b)

x-intercept:

It is the value of x where f(x)=0

so, the point where curve intersects on x-axis

and we get

$2x^2-4=0$

$x=\sqrt{2}$

and

$x=-5$

(c)

Increasing interval:

where curve is moving upward

we can see that

$(0,\infty)$

Decreasing interval:

where curve is moving downward

we get

$(-\infty,-1)U(-1,0)$

Constant:

constant means horizontal line

there is no horizontal line here

so, it does not exist

(D)

End behavior:

when x-->+inf

y is moving upward

so, y---->+inf

when x-->-inf

y is moving upward

so, y---->+inf

(E)

we can see that curve jupms at x=-1

so, there is discontinuity at x=-1

and this is jump type of discontinuity

(F)

For odd:

f(-x)=-f(x)

For even:

f(-x)=f(x)

we can see that none of them holds true

so, this is neither

3 0

3 years ago