Question

lets talk math

Answer 1

@ranga

Answer 2

x is the row number.
Number of seats in row x is: N = 10 + 2(x-1)

Answer 3

they don't say, but they want "x" to stand for the row number.

when they say
first row's seats are modeled by the function f(x) = 10
that is true only for x=1. f(1)=10

Answer 4

hello anyone there?

Answer 5

They want you to come up with a function that tells us how many seats are in row x

can you do that ?

Answer 6

so how do i make an equation for 20th row

Answer 7

It would be good to think this through.

Answer 8

You first come up with a general function that tells how many seats are there in row "x". Then you plug x = 20 to find the number of seats in the 2oth row.

Answer 9

Can you make sense of what this is telling you:
additional seats a row has is modeled by the function s(x) = 2(x - 1).

Answer 10

yes I can

Answer 11

The "additional seats" they are referring to is additional seats compared to the first row.

Answer 12

how would you use it to figure out how many seats are in row 2 ?

Answer 13

2(2-1)? right?

Answer 14

which means what ?

Answer 15

i plug in whatever number they need so the equation will look like this s(X)=2(20-1)

Answer 16

yes, but what does the number that you get mean ?

Answer 17

uhh thats how many people will be in that row right?.

Answer 18

for row 2, you found
2(2-1)? right?

that simplifies to 2*1= 2

in other words s(2) = 2

look at what they told you
The number of additional seats a row has is modeled by the function s(x) = 2(x - 1).

any ideas ?

Answer 19

ummm i dont know whats wrong

Answer 20

You have to know what this means
The number of additional seats a row

for row 2, that phrase can be reworded as

the number of additional seats in row 2 is 2

any idea what that means?

Answer 21

oh ok so add 20 right? pls bare continue baring with me

Answer 22

we will get to row 20 in a little bit.

The first step is understanding what is going on.
You are in a theater.
The first row has 10 seats.

They tell you
To give everyone a good view, each row must have two more seats than the row before it
Do you know what that means? In other words, how many seats in row 2 ?

Answer 23

12

Answer 24

yes. and 12 is 10+2
the 2 is the 2 additional seats in row 2

the s(x)= 2(x-1) is telling you that row 2 will have 2 more seats than the first row

Answer 25

how many additional seats are in row 3 ?

Answer 26

14

Answer 27

yes, there are 14 total seats in row 3.

But how many "additional" seats ? use s(x)= 2(x-1)

Answer 28

2

Answer 29

use s(x)= 2(x-1)
with x= 3 (because we are doing row 3)

Answer 30

im sorry am i wrong?

Answer 31

use s(x)= 2(x-1)
with x= 3 (because we are doing row 3)

Answer 32

ok this formula doesnt work

Answer 33

i got 4

Answer 34

The formula is telling you how many seats more than the *first row*

here is what we know
first row 10
2nd row 12 2 more than the first row
3rd row 14 2 more than the 2nd row, **4** more than the first row

Answer 35

now if you wanted to know how many seats in the 4th row (and you did not already calculate how many are in the 3rd row), you can use the formula to find how many seats more than the first row and then add 10.

Answer 36

4th row: s(4) = 2(4-1) = 2*3= 6

row 4 will have 6 more seats than the first row. It will have 6+10 = 16 seats

Does this give you an idea how to do row 20 ?

Answer 37

Number of seats in any row = Number of seats in first row + Number of additional seats in that row compared to the first row.
N = 10 + 2(x - 1)
N = 2x + 8

Answer 38

ohh so s20=2(20-1) so the 20th roq has 38 more seats than the one before

Answer 39

almost. 38 more seats than *THE FIRST ROW*

Answer 40

so 10+38?

Answer 41

yes

Answer 42

But here they are asking you to first come up with an equation to find the number of seats in any row and then later in the 20th row. So it is better to come up with the general function first.

Answer 43

maybe woohoo can review what we have done, and come up with an equation?

Answer 44

uhh so s20=2(20-1)+10? idk is that right

Answer 45

yes. That is for x=20. You can "tweak" it to work for any row number by using x instead of 20.

Answer 46

They want you to
create an equation to predict the number of seats in any row.

Answer 47

To be clear, you have to write an equation that uses x (not just 20)

can you change
s(20)=2(20-1)+10
to use "x" instead of 20? (replace every 20 with an x)

Answer 48

oh nice thanks!!