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leva [86]
3 years ago
14

How many 7 digit phone numbers are there assuming the first digit can't be a 0 or a 1?

Mathematics
1 answer:
Anettt [7]3 years ago
7 0
The first digit can be any one of the numbers 2-9 That a total of 8 numbers.

The next 6 digits can be any permutation of 6  from the numbers  0 to 9.
(10 numbers)

nPr  =  n! / r!

so here we have  10P6  = 10! / 6!  =  10*9*8*7  =  5040

So final answer  is 8 * 5040 = 40,320
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Which equation represents the data in
klasskru [66]

Answer:

y = 2x - 4

Step-by-step explanation:

The equations are put in slope intercept form

Slope intercept form: y = mx + b

Where m = slope and b = y intersect

So in order to find the equation of the data represented by the table we will have to find the slope and y intercept

Let's begin!

First let's find the slope

We can find the slope by using the slope formula

m = (y2 - y1) / (x2 - x1) where the x and y values are derived from coordinates from the table

The points chosen may vary but I have chosen the points (0,-4) and (1,-2)

Now that we have chosen the points we will use to find the slope let's define the variables

remember coordinates are written like this: (x,y)

The x value of the second coordinate is 1 so x2 = 1

The x value of the first coordinate is 0

So x1 = 0

The y value of the second coordinate is -2 so y2 = -2

The y value of the first coordinate is -4

So y1 = -4

Now that we have defined each variable let's plug in the values into the formula

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

Variables: x2 = 1, x1 = 0, y2 = -2, y1 = -4

Substitute values

m = (-2 - (-4) / ( 1 - 0 )

Evaluate

The negative signs cancel out on top and it changes to +4

m = (-2 + 4)/(1-0)

Add top values

m = 2/(1-0)

Subtract bottom numbers

m = 2/1

Simplify fraction

m = 2

So we can conclude that the slope (m) = 2

Now let's find the y intercept or "b"

The y intercept is the value of y when x = 0

If you look at the table when x = 0 y = -4 meaning that the y intercept or "b" is -4

Now that we have found everything let's find the equation of the data represented by the table

The equation is in slope intercept form

y = mx + b

Define variables

m = 2 and b = -4

Substitute values

y = 2x - 4

The equation is y = 2x - 4

4 0
3 years ago
Can someone help me ?
GuDViN [60]

Answer:

-5,-3,-1,1,3

Step-by-step explanation:

range= y

really need brainliest!!

4 0
3 years ago
Read 2 more answers
Solve for y, 12x-20y=180​
nydimaria [60]

Answer:

y=35x−9

Step-by-step explanation:

Step 1: Add -12x to both sides.

12x−20y+−12x=180+−12x

−20y=−12x+180

Step 2: Divide both sides by -20.

−20y−20=−12x+180−20

y=35x−9

4 0
3 years ago
Read 2 more answers
After a reflection, can A=A'?
motikmotik
NO It can not!

Reason: the reason is because since both are the same , it will equal the mostly 0! So it wouldn’t make sense. So no!

Hoped I help mark brainly it would help me a lot!
4 0
3 years ago
2 2/3 * 3/4 answer that ​
Nataly_w [17]

answer = 2

You can just use a calculator unless you need to show your work

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3 years ago
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