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
babunello [35]
3 years ago
12

Seven pens and two pencils costs $6.59. seven pens and five cost $7.55. Find the cost of one pencil and the cost of one pen.

Mathematics
1 answer:
serg [7]3 years ago
5 0
Let one pen be x and one pencil as y, we can produce two equations in terms of x and y

7x+2y=6.59 ------> Equation 1
7x+5y=7.55 ------> Equation 2

We can use either Elimination or Substitution method. Let's try the substitution method

Rearranging equation one to get 7x=6.59-2y and substitute into equation 2, gives
(6.59-2y)+5y=7.55
6.59+3y=7.55
3y=7.55-6.59
3y=0.96
y=0.32

We can use either equation one or equation to work out x

7x+2(0.32)=6.59
7x=6.59-0.64
x=0.85

The price of one pen is $0.85
The price of one pencil is $0.32
You might be interested in
It is said that dogs age seven years for every people year.Masons dog,sheep,was born on masons eighth birthday.When mason was ni
Lady_Fox [76]

Answer:

28

Step-by-step explanation:

so, if mason is 9 and the sheep is 7 year old in dog years

we have to do 7*4 ,because 9,10,11,12=4 that's why u multiply it by 4,and 7 because thats how many years dogs ages for every person that turns a year age

3 0
3 years ago
Find the slope of the line that passes through the given points.
sammy [17]

Answer: -1/6

Step-by-step explanation:

slope= change of y over change of x

3-4/ 5--1=

-1/6

Hope this helps!

8 0
2 years ago
Read 2 more answers
How many solutions does this equation have x^4 - 6x^2 -7 = 0
NNADVOKAT [17]

Answer:

2 solutions

Step-by-step explanation:

x^4-6x^2-7=0

Replace x^2 by y

(x^2)^2-6x^2-7=0

y^2-6y-7=0

D=b^2-4ac= (-6)^2-4*1*(-7)= 36+28=64

sqrtD=8

y1=(-b-sqrtD)/2a=-2/2=-1

y2= (-b+sqrtD)/2a=14/2=7

x^2=-1(n0 roots)    x^2=7 x=sqrt7 or x=-sqrt7

2 roots

5 0
3 years ago
Need help with this question about amplitude
lesantik [10]

Step-by-step explanation:

the amplitude is the height of the wave.

like with sound - the further away you are, the lower the volume of the sound (as the sound volume is the indicator of the amplitude of a sound wave, or the brightness of a light is the indicator of the amplitude of a light wave).

the same for any other type of wave (like the seismic wave of an earthquake).

so, the larger the distance, normally the smaller the amplitude.

4 0
1 year ago
Abigail”s car used 9 gallons of gas to travel 378 miles. How many gallons of gas would she need to travel 210 miles?
pochemuha

Answer: 5 gallons

Step-by-step explanation:

First, we need to know how many miles we can get by on a gallon of gas. To find this, we need to divide 378 miles by 9 gallons.

378/9 = 42

42 miles per gallon.

Now, we need to find how many gallons of gas it will take Abigail to travel 210. To find this, we simply divide 210 by 42.

210/42 = 5

It will take Abigail 5 gallons of gas to travel 210 miles.

3 0
3 years ago
Read 2 more answers
Other questions:
  • 0.14 repeating decimals
    12·1 answer
  • B) Write 25 x 10^6 in standard form.
    14·1 answer
  • Solve the system by the elimination method.
    12·1 answer
  • The students in Roberto's school are painting a mural that will be 15 feet by 8 feet. First they make a scale drawing of the mur
    11·1 answer
  • What is the value of x in the equation? 5 5/6 x + 2 2/3 = 12
    11·1 answer
  • What is the value of <img src="https://tex.z-dn.net/?f=%5Cfrac%7Bx2%7D%7By1%7D" id="TexFormula1" title="\frac{x2}{y1}" alt="\fra
    15·1 answer
  • Someone help me please
    5·1 answer
  • Convert 576,904,320 using scientific notation
    13·1 answer
  • What is the volume of the triangular prism in cubic centimeters?
    9·1 answer
  • Please help me understand
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!