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3 years ago

A cross-country train travels at a steady speed. It covers 15 miles in 20

Mathematics

1 answer:

skelet666 [1.2K]3 years ago

5 0

Answer:

i think its 225 but i can still be wrong

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Use the terms below to create a linear equation with a solution of x = 10<br> Terms: x 2 4 5

yulyashka [42]

Answer:

$x = \frac{4 * 5}{2}$

Step-by-step explanation:

x = 10

x = 20 / 2

x = 4*5 / 2

5 0

3 years ago

For each of the following functions, determine if they are injective. Also determine if theyare surjective. Also determine if th

timurjin [86]

Answer:

Check below

Step-by-step explanation:

1. Definition for intervals

$(a,b)=\left \{ x\in\Re : a$

2. Functions

1) $\Re \rightarrow \Re \\ f(x)=x$

Let's perform graph tests.

That's an one to one, injective function. Look how any horizontal line touches that only once. Also, It's a surjective and a bijective one.

2) $\Re\geq0\rightarrow\Re , f(x)=x+1\\$

Injective, surjective and bijective.

Injective: a horizontal line crosses the graph in one point.

3) $f:\Re\geq 0\rightarrow\Re, f(x) = cos(x)$

The cosine function is not injective, bijective nor surjective.

4) $f:\Re\rightarrow\Re \:f(x)=ex$

Since e, is euler number it's a constant. It's also injective, surjective and bijective.

5) Quite unclear format

$6) \:f:\Re\rightarrow(0,\infty), f(x) =ex$

Despite the Restriction for the CoDomain, the function remains injective, surjective and therefore bijective.

$7) f:\Re\geq 0 \rightarrow \Re\geq0, f(x) =x^{4}$

Not injective nor surjective therefore not bijective too.

$8).f:\{-1,2,-3\}}\rightarrow \{1,4,9\}, f(x) =x^{2}$

$f(-1)=1, f(2)=4, f(-3)=9$

Injective (one to one), Surjective, and Bijective.

$10) f:\Re\geq 0\rightarrow [-1,1], f(x)= cos(x)\\-1=cos(x) \therefore x=\pi,3\pi,5\pi,etc.$

Surjective.

$11.f:R\geq 0[-1,1], f(x) = 0\\$

Surjective

12.f: US Citizens→Z, f(x) = the SSN of x.

General function

13.f: US Zip Codes→US States, f(x) = The state that x belongs to.

Surjective

7 0

3 years ago

mica and denise are reading the same novel. mica has read 1/2 of the novel, and denise has read 1/3 of the novel. how much more

vovangra [49]

You convert the fractions into 6ths. So 1/3. You would multiply both parts by 2 (top and bottom denominators) and that would be 2/6. 1/2 of 6 is 3/6. So the answer would be 1/6

7 0

3 years ago

Read 2 more answers

What are the slope and the y-intercept of the linear function that is represented by the table?

Hunter-Best [27]

Answer:

Slope is -2/5 and y-intercept is -1/3

Step-by-step explanation:

To get the slope, we pick any two points and apply the slope formula

The slope formula is;

m = (y2-y1)/(x2-x1)

To get the slope, we select any two points

That will be;

(-3/4, -1/30) and (1/4,-13/30)

Substituting these in the slope formula, we have:

m = (-13/30 + 1/30)/(1/4 + 3/4)

m = 12/30 = -2/5

Generally, the equation of a straight line is;

y = mx + b

m is slope and b is the y-intercept

We already have the slope, to get the y-intercept, we select any of the points

-3/5 = -2/5(2/3) + b

= -3/5 + 4/15 = b

b = (-9 + 4)/15 = -5/15 = -1/3

Slope is -2/5 and y-intercept is -1/3

6 0

3 years ago

Read 2 more answers

What is the sum of 3.14and 4.83

-Dominant- [34]

Answer:

7.97

Step-by-step explanation:

3.14

+4.83

---------

7.97

4 0

3 years ago