Answer:
A book is worth $1 and a DVD is worth $12.
Step-by-step explanation:
The equations (2 unknowns and two equations, d is for a DVD and b is for a book):
For David: 3d+4b=40
For Anna: d+6b=18
Now multiply the second equation with -3 and add to the first equation:
3d+4b=40
−3d−18b=−54
Combined equation: −14b=−14 and b=1 (means that each book is worth $1).
Now for DVD price, use the second equation:
d=18−6 or d=12 (means that each DVD is worth $12).
A book is worth $1 and a DVD is worth $12.
Answer:
The approximate percentage is 25%.
Step-by-step explanation:
The initial population was = 12089 rounded off to 12000.
The final population is = 15025 rounded off to 15000.
Change in population = 
So, the approximate percent increase is =
= 25%.
Answer:
9.) Its equilateral
7.) 24
Step-by-step explanation:
Sorry I only have the answer for 7 and 9.
