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
Marina86 [1]
2 years ago
9

Hi how do I solve this simultaneous equation

Mathematics
1 answer:
WITCHER [35]2 years ago
8 0

Answer:

M (-3, -5/2)

N (3, -1)

Step-by-step explanation:

Solve the first equation for x.

4y = x − 7

x = 4y + 7

Substitute into the second equation.

x² + xy = 4 + 2y²

(4y + 7)² + (4y + 7)y = 4 + 2y²

Simplify.

16y² + 56y + 49 + 4y² + 7y = 4 + 2y²

18y² + 63y + 45 = 0

2y² + 7y + 5 = 0

Factor.

(y + 1) (2y + 5) = 0

y = -1 or -5/2

Plug back into the first equation to find x.

x = 4(-1) + 7 = 3

x = 4(-5/2) + 7 = -3

M (-3, -5/2)

N (3, -1)

You might be interested in
10. Saul works two part-time jobs. Last week, he worked 14 hours at a shoe store, and 19
Sedbober [7]

Answer:

shoe store $7.80/hour

telemarketer: $6.90/hour

Step-by-step explanation:

Let s = hourly salary at the shoe store.

Let t = hourly salary as a telemarketer.

14s + 19t = 240.3

19s + 22t = 300

Multiply both sides of the first equation by 19. Multiply both sides of the second equation by -14. Then add them.

         266s + 361t = 4565.7

(+)     -266s - 308t = -4200

----------------------------------------

                       53t = 365.7

t = 6.9

Substitute 6.9 for t in the first equation and solve for s.

14s + 19(6.9) = 240.3

14s + 131.1 = 240.3

14s = 109.2

s = 7.8

Answer:

shoe store $7.80/hour

telemarketer: $6.90/hour

6 0
3 years ago
Landry earned $2,300 over the summer and decided to invest it in an account that earns 4% annual compound interest. If Landry do
solniwko [45]

Answer:

Landry will have $5039.58

Step-by-step explanation:

compound interest formula: amount = p(1 + \frac{r}{n})^{nt}

p= principal ($2,300)

r= interest rate as a decimal (4% = 0.04)

n= number of times the principal is compounded per year (annually = once per year so 1 time per year)

t= time in years (20 years)

new equation: amount = 2300(1+\frac{0.04}{1} )^{1*20}

That equation equals $2,739.58 which you add to the principal.

$2,739.58 + $2,300 = $5039.58

hope this helps :) the equations aren't showing up right :(

6 0
3 years ago
Read 2 more answers
Which number produces a rational number when multiplied by 0.4
Katyanochek1 [597]
A, B and D are already rational numbers, 0.4 itself is a rational number, two rational numbers make a product of rational number. 
So A, B, D are the correct choices. 

Are you sure it asks for rational numbers, not irrational number?
7 0
3 years ago
Read 2 more answers
Multiply and divide These
Elan Coil [88]

Answer:

1. 1 2.-1 3.-1 4.1 5.18 6.5

Step-by-step explanation:

that 8s answer gegegge

3 0
3 years ago
Can someone please help with this 7th grade math question?
pogonyaev

Answer:

B,,,,,,,,,  2, 6, 10, and -8

Step-by-step explanation:

Coefficients are any numbers part of an equation

8 0
3 years ago
Other questions:
  • Find the value of s for which WXYZ is a parallelogram
    9·2 answers
  • The largest angle of a triangle measures 60 more degrees than the smallest angle. The middle angle measures 30 more degrees than
    13·1 answer
  • is it possible to construct a triangle with the given side lengths 35, 120 and 125 units if not explain why not ​
    13·2 answers
  • Which part of a pictograph provides an overview of the information in the chart?
    11·1 answer
  • Mark and Tony have a total of 121 baseball cards. Tony has 5 more than three times Mark's amount. How many cards does Mark have?
    10·2 answers
  • Every answer I have typed in is wrong but what is. <br> 2/12 simplified
    6·2 answers
  • 1.6 + 3 x 4 - 2 divided by 2<br> An PEMDAS question, pretty easy!
    5·2 answers
  • I’ll give brainlist but please help it’s a quiz.
    13·2 answers
  • Carlos harvests cassavas at a constant rate. He needs 353535 minutes to harvest a total of 151515 cassavas.
    14·2 answers
  • 2. Find the volume of the storage container shown. Round to the nearest tenth.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!