1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Finger [1]
3 years ago
5

David bought 3 dvds and 4 books for $40 at a yard sale. Anna bought 1 dvd and 6 books for $18. How much did each dvd and book co

st?
Mathematics
1 answer:
Ber [7]3 years ago
8 0

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.

You might be interested in
A bookstore sells paperback fiction books in excellent condition for $2.50 and in fair condition for $0.50. Write an expression
Rama09 [41]

Answer:

d

Step-by-step explanation:a

3 0
3 years ago
Whats the capacity of a water bottle thats 8 inches
suter [353]
1 pt; or 1 pint seems most reasonable here.

8 0
3 years ago
The inequality below represents h, the number of hours Ellie need to work this week to earn at least $360 by the end of the mont
Gnom [1K]

Answer:

The answer to your question is 10 hours.

Step-by-step explanation:

Inequality                            12h + 240 > 360

Solve the inequality as if it was an equation

                                           12h > 360 - 240

                                           12h > 120

                                           h > 120 / 12

                                           h = 10 hours

Let's evaluate some number of hours

If h = 3                        12(3) + 240 > 360

                                  36 + 240 > 360

                                          276 > 360     Incorrect, she needs to work more

                                                                 than 3 hours

If h = 5                         12(5) + 240 > 360

                                   60 + 240 > 360

                                           300 > 360     Incorrect, she needs to work more

                                                                 than 5 hours

If h = 7                          12(7) + 240 > 360  

                                    84 + 240 > 360

                                          324 > 360      Incorrect she needs to work more

                                                                 than 7 hours

If h = 11                          12(11) + 240 > 360  

                                     132 + 240 > 360

                                              372 > 360   Correct, she needs to work at least

                                                                   10 hours.                                              

7 0
3 years ago
HELP ME PLS NEED IT QOUIKC
nexus9112 [7]

Answer: 7.08 cm2

Step-by-step explanation:

6 0
2 years ago
Hello! could someone graph these as a Linear System, please?
BabaBlast [244]

Here it is brainliest please

8 0
3 years ago
Other questions:
  • Given independent events A and B such that P(A) = 0.3 and P (B) = 0.5, which of the following is a correct statement?
    14·1 answer
  • Giving brainliest please help
    13·1 answer
  • Which are perfect cubes?
    12·2 answers
  • A privately owned lake contains two types of game fish, bass and trout. The owner provides two types of food, A and B, for these
    10·1 answer
  • −4.5=−0.5(x−7.1)<br> solve for x
    7·2 answers
  • Find the area of the circle below. Use 3.14 for pi
    10·1 answer
  • Amber made 15 pies after working 3 hours how many pies did amber prepare if she worked 4 hours
    12·1 answer
  • Which equation has infinitely many solutions? a 12 + 4x = 6x + 10 - 2x
    8·1 answer
  • Find the unit rate. 12 laps in 30minutes. <br> Asking for fraction
    9·1 answer
  • 1. En una biblioteca quieren comprar una computadora que
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!