Ken paid for $12 for two magazines. the cost of each magazine was a multiple of 3. what is mare the possible prices of the magazines?

So the possibilities are

$12 and $ 0    ,    $9 and $ 3      , $6 and $6

Step-by-step explanation:

Given:

Total Magazines = 2

Price = $ 12

To Find:

Possible Prices of magazines = ?

Solution:

As it is given that Prices of magazines is multiples of 3

So

Multiples of 3 up till 12 are  

0, 3 , 6 , 9 , 12

Now

Total Price of magazine is $12

Now The possible prices of the magazines are

First Possibility:

If price of first magazine is $12 then second would be $0 (free)

First possible price $12 and $0

Second Possibility:

If price of first magazine is $9 then second would be $3

Second possible price $3 and $9

Third Possibility:

If price of first magazine is $6 then second would be $6

Third possible price $6 and $6

So the possibilities are

$12 and $ 0    ,    $9 and $ 3      , $6 and $6

(0,-3) see attached graph

step-by-step explanation:

a. to solve the system, graph the two equations.

x = y+3 becomes y=x-3 has m=1/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move up 1 unit and 1 unit to the right. plot a point and connect.

y=-4x+3 has m =-4/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move down four units and to the right 1 unit. plot a point and connect.

the solution is the point (x,y) where the two lines intersect. by the graph below it is (0,-3).

b. to solve by substitution, substitute y = -4x-3 into x= y+3

x= (-4x-3) +3

x=-4x

5x=0

x=0

now substitute x = 0 back in to find y.

y= -4(0)-3

y=0-3

y=-3

solution is (0,-3)

c. use elimination by adding the equations together.

x-y=3

4x+y=-3

5x=0

x=0

then substitute into one equation to find y.

y=-4(0)-3

y=-3