Trong mặt phẳng tọa độ oxy, cho đường thẳng d : 3x+y-9=0

Correct option is 7

Step-by-step explanation:

Using the section formula, if a point (x,y) divides the line joining the points (x

1

,y

1

) and (x

2

,y

2

) in the ratio m:n, then (x,y)=(

m+n

mx

2

+nx

1

,

m+n

my

2

+ny

1

)

Let the ratio be k:1

Substituting (x

1

,y

1

)=(1,3) and (x

2

,y

2

)=(2,7) in thesection formula, we get the point which divides as (

k+1

k(2)+1(1)

,

k+1

k(7)+1(3)

)=(

k+1

2k+1

,

k+1

7k+3

)

Since this point lies on the line 3x+y−9=0, we have

3(

k+1

2k+1

)+

k+1

7k+3

−9=0

=>6k+3+7k+3−9k−9=0

4k−3=0

k=

4

3

Hence, the ratio is a:b=3:4 internally.

So a+b=7

step-by-step explanation:

ok one would be money, and the other would be refreshments or something similar. if each bag of popcorn is 5.00 and each drink is half of that that means drinks are 2.50 the proper way to do that would to look and see how much of each you can buy without exceeding a limit of 30.00