Write an equation with a slope of -1/2 in each form.
point-slope form
slope-intercept form.

For the case of a line through

(

2

,

7

)

and

(

1

,

−

4

)

we have

slope

m

=

Δ

y

Δ

x

=

−

4

−

7

1

−

2

=

−

11

−

1

=

11

Using the point

(

2

,

7

)

we can write the equation of the line in point slope form as:

y

−

7

=

m

(

x

−

2

)

where the slope

m

=

11

.

That is:

y

−

7

=

11

(

x

−

2

)

To get point intercept form, first expand the right hand side so...

y

−

7

=

11

x

−

(

11

⋅

2

)

=

11

x

−

22

Then add

7

to both sides to get:

y

=

11

x

−

15

=

11

x

+

(

−

15

)

This is point intercept (

y

=

m

x

+

c

) form with slope

m

=

11

and intercept

c

=

−

15

.

.

step-by-step explanation:

step-by-step explanation: so we look at the formula un = a + (n-1)d

un is the amount of seats

n is the nth term aka row number

a is the original sequence/row number

d is the difference between each term

so in this a=22 d=6 and n can remain as n because we are simply formjng a rule

lets put these in the equation

un=22+(n-1)(6)

this is your answer to part a

however

lets double check that this is correct, we'll try putting it into the second term

un=a+(n-1)d

u2=22+(2-1)(6)

u2=22+6

u2=28

as the question said the second row has 28 seats so now we know the formula we made is correct.

as for part b

un=a+(n-1)

its asking us to find a row with 100 seats.

remember un was the amount of seata so all we do is substitute this in.

un=100 a=22 d=6

un=a+(n-1)d

100=22+(n-1)(6)

so now we simplify to find n which is the row number.

100-22=22+(n-1)(6)-22

78=(n-1)(6)

78/6=(n-1)(6)/6

13=n-1

13+1=n-1+1

14=n

so now we know that in the 14th row there is 100 seats.

hope this and that you understood! its my first time using the app or anyone out on here : p its also me to revise so a bunch! ask more questions if you dont understand ☺