<< Chapter < Page Chapter >> Page >

5 x y = 4 x + 6 y = 2 and ( 4 , 0 )

Got questions? Get instant answers now!

−3 x 5 y = 13   x + 4 y = 10 and ( −6 , 1 )

Yes

Got questions? Get instant answers now!

3 x + 7 y = 1 2 x + 4 y = 0 and ( 2 , 3 )

Got questions? Get instant answers now!

−2 x + 5 y = 7    2 x + 9 y = 7 and ( −1 , 1 )

Yes

Got questions? Get instant answers now!

x + 8 y = 43 3 x −2 y = −1 and ( 3 , 5 )

Got questions? Get instant answers now!

For the following exercises, solve each system by substitution.

   x + 3 y = 5 2 x + 3 y = 4

( −1 , 2 )

Got questions? Get instant answers now!

  3 x −2 y = 18 5 x + 10 y = −10

Got questions? Get instant answers now!

4 x + 2 y = −10 3 x + 9 y = 0

( −3 , 1 )

Got questions? Get instant answers now!

2 x + 4 y = −3.8 9 x −5 y = 1.3

Got questions? Get instant answers now!

2 x + 3 y = 1.2 3 x 6 y = 1.8

( 3 5 , 0 )

Got questions? Get instant answers now!

    x −0.2 y = 1 −10 x + 2 y = 5

Got questions? Get instant answers now!

     3 x + 5 y = 9 30 x + 50 y = −90

No solutions exist.

Got questions? Get instant answers now!

  −3 x + y = 2 12 x −4 y = −8

Got questions? Get instant answers now!

1 2 x + 1 3 y = 16 1 6 x + 1 4 y = 9

( 72 5 , 132 5 )

Got questions? Get instant answers now!

1 4 x + 3 2 y = 11 1 8 x + 1 3 y = 3

Got questions? Get instant answers now!

For the following exercises, solve each system by addition.

−2 x + 5 y = −42    7 x + 2 y = 30

( 6 , −6 )

Got questions? Get instant answers now!

6 x −5 y = −34 2 x + 6 y = 4

Got questions? Get instant answers now!

     5 x y = −2.6 −4 x −6 y = 1.4

( 1 2 , 1 10 )

Got questions? Get instant answers now!

7 x −2 y = 3 4 x + 5 y = 3.25

Got questions? Get instant answers now!

  −x + 2 y = −1 5 x −10 y = 6

No solutions exist.

Got questions? Get instant answers now!

       7 x + 6 y = 2 −28 x −24 y = −8

Got questions? Get instant answers now!

5 6 x + 1 4 y = 0 1 8 x 1 2 y = 43 120

( 1 5 , 2 3 )

Got questions? Get instant answers now!

   1 3 x + 1 9 y = 2 9 1 2 x + 4 5 y = 1 3

Got questions? Get instant answers now!

−0.2 x + 0.4 y = 0.6             x −2 y = −3

( x , x + 3 2 )

Got questions? Get instant answers now!

−0.1 x + 0.2 y = 0.6       5 x −10 y = 1

Got questions? Get instant answers now!

For the following exercises, solve each system by any method.

5 x + 9 y = 16    x + 2 y = 4

( −4 , 4 )

Got questions? Get instant answers now!

6 x −8 y = −0.6 3 x + 2 y = 0.9

Got questions? Get instant answers now!

5 x −2 y = 2.25 7 x −4 y = 3

( 1 2 , 1 8 )

Got questions? Get instant answers now!

   x 5 12 y = 55 12 −6 x + 5 2 y = 55 2

Got questions? Get instant answers now!

7 x −4 y = 7 6 2 x + 4 y = 1 3

( 1 6 , 0 )

Got questions? Get instant answers now!

3 x + 6 y = 11 2 x + 4 y = 9

Got questions? Get instant answers now!

       7 3 x 1 6 y = 2 21 6 x + 3 12 y = −3

( x , 2 ( 7 x −6 ) )

Got questions? Get instant answers now!

1 2 x + 1 3 y = 1 3 3 2 x + 1 4 y = 1 8

Got questions? Get instant answers now!

2.2 x + 1.3 y = −0.1 4.2 x + 4.2 y = 2.1

( 5 6 , 4 3 )

Got questions? Get instant answers now!

  0.1 x + 0.2 y = 2 0.35 x −0.3 y = 0

Got questions? Get instant answers now!

Graphical

For the following exercises, graph the system of equations and state whether the system is consistent, inconsistent, or dependent and whether the system has one solution, no solution, or infinite solutions.

3 x y = 0.6 x −2 y = 1.3

Consistent with one solution

Got questions? Get instant answers now!

x + 2 y = 4   2 x −4 y = 1

Got questions? Get instant answers now!

   x + 2 y = 7 2 x + 6 y = 12

Consistent with one solution

Got questions? Get instant answers now!

3 x −5 y = 7    x −2 y = 3

Got questions? Get instant answers now!

   3 x −2 y = 5 −9 x + 6 y = −15

Dependent with infinitely many solutions

Got questions? Get instant answers now!

Technology

For the following exercises, use the intersect function on a graphing device to solve each system. Round all answers to the nearest hundredth.

    0.1 x + 0.2 y = 0.3 −0.3 x + 0.5 y = 1

Got questions? Get instant answers now!

−0.01 x + 0.12 y = 0.62 0.15 x + 0.20 y = 0.52

( −3.08 , 4.91 )

Got questions? Get instant answers now!

0.5 x + 0.3 y = 4 0.25 x −0.9 y = 0.46

Got questions? Get instant answers now!

0.15 x + 0.27 y = 0.39 −0.34 x + 0.56 y = 1.8

( −1.52 , 2.29 )

Got questions? Get instant answers now!

−0.71 x + 0.92 y = 0.13 0.83 x + 0.05 y = 2.1

Got questions? Get instant answers now!

Extensions

For the following exercises, solve each system in terms of A , B , C , D , E , and F where A F are nonzero numbers. Note that A B and A E B D .

x + y = A x y = B

( A + B 2 , A B 2 )

Got questions? Get instant answers now!

A x + y = 0 B x + y = 1

( −1 A B , A A B )

Got questions? Get instant answers now!

A x + B y = C D x + E y = F

( C E B F B D A E , A F C D B D A E )

Got questions? Get instant answers now!

Real-world applications

For the following exercises, solve for the desired quantity.

A stuffed animal business has a total cost of production C = 12 x + 30 and a revenue function R = 20 x . Find the break-even point.

Got questions? Get instant answers now!

A fast-food restaurant has a cost of production C ( x ) = 11 x + 120 and a revenue function R ( x ) = 5 x . When does the company start to turn a profit?

They never turn a profit.

Got questions? Get instant answers now!

A cell phone factory has a cost of production C ( x ) = 150 x + 10 , 000 and a revenue function R ( x ) = 200 x . What is the break-even point?

Got questions? Get instant answers now!

A musician charges C ( x ) = 64 x + 20,000 , where x is the total number of attendees at the concert. The venue charges $80 per ticket. After how many people buy tickets does the venue break even, and what is the value of the total tickets sold at that point?

( 1 , 250 , 100 , 000 )

Got questions? Get instant answers now!

A guitar factory has a cost of production C ( x ) = 75 x + 50,000. If the company needs to break even after 150 units sold, at what price should they sell each guitar? Round up to the nearest dollar, and write the revenue function.

Got questions? Get instant answers now!

Questions & Answers

Why is b in the answer
Dahsolar Reply
how do you work it out?
Brad Reply
answer
Ernest
heheheehe
Nitin
(Pcos∅+qsin∅)/(pcos∅-psin∅)
John Reply
how to do that?
Rosemary Reply
what is it about?
Amoah
how to answer the activity
Chabelita Reply
how to solve the activity
Chabelita
solve for X,,4^X-6(2^)-16=0
Alieu Reply
x4xminus 2
Lominate
sobhan Singh jina uniwarcity tignomatry ka long answers tile questions
harish Reply
t he silly nut company makes two mixtures of nuts: mixture a and mixture b. a pound of mixture a contains 12 oz of peanuts, 3 oz of almonds and 1 oz of cashews and sells for $4. a pound of mixture b contains 12 oz of peanuts, 2 oz of almonds and 2 oz of cashews and sells for $5. the company has 1080
ZAHRO Reply
If  , , are the roots of the equation 3 2 0, x px qx r     Find the value of 1  .
Swetha Reply
Parts of a pole were painted red, blue and yellow. 3/5 of the pole was red and 7/8 was painted blue. What part was painted yellow?
Patrick Reply
Parts of the pole was painted red, blue and yellow. 3 /5 of the pole was red and 7 /8 was painted blue. What part was painted yellow?
Patrick
how I can simplify algebraic expressions
Katleho Reply
Lairene and Mae are joking that their combined ages equal Sam’s age. If Lairene is twice Mae’s age and Sam is 69 yrs old, what are Lairene’s and Mae’s ages?
Mary Reply
23yrs
Yeboah
lairenea's age is 23yrs
ACKA
hy
Katleho
Ello everyone
Katleho
Laurene is 46 yrs and Mae is 23 is
Solomon
hey people
christopher
age does not matter
christopher
solve for X, 4^x-6(2*)-16=0
Alieu
prove`x^3-3x-2cosA=0 (-π<A<=π
Mayank Reply
create a lesson plan about this lesson
Rose Reply
Excusme but what are you wrot?

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Algebra and trigonometry. OpenStax CNX. Nov 14, 2016 Download for free at https://legacy.cnx.org/content/col11758/1.6
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Algebra and trigonometry' conversation and receive update notifications?

Ask