Answer: One DVD is $12 and one book is $1
Step-by-step explanation:
Let the DVD be d and the book be b.
Case 1:
3d + 4b = $40.......(1)
Case 2:
1d + 6b = $18........... (2)
In this equations above, I intend to eliminate variable d, so I'm going to multiply the coefficient of d in (1) to multiply (2)
3 × (1d + 6b = 18)
3d + 18b = 54........ .(3)
Then, subtract (1) from (3)
3d + 18b = 54
- ( 3d + 4b = 40)
3d - 3d + 18b - 4b = 54 - 40
0 + 14b = 14
b = 14/14
b = 1.
Then substitute 1 for b in (2)
1d + 6(1) = 18
d + 6 = 18
d = 18 - 6
d = 12.
(d,b) = (12,1)
Answer:
Below
Step-by-step explanation:
9 
Think about it think 6x5 or higher then you will get you answer by doing that
You need to add a -1
We can find this by setting up the equation like so
x + (-6) + 12 + 15 / 4 = 5
x + 21 = 20
x = 20 -21
x = -1
Now if we insert -1 where x is located in the equation, you will get a means of 5