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3 years ago

Solve the simultaneous equations x + 6y = 20 x + 3y = 14 x = Y=

Mathematics

2 answers:

antoniya [11.8K]3 years ago

7 0

Answer:

x=8

Y=2

(x,y)=(8,2)

Step-by-step explanation:

x+6y=20

x+3y=14

solve the equation for x

x+6y=20

x=14-3y

substitute the given value of x into the equation

x+6y=20

14-3y+6y=20

14+3y=20

3y=20-14

3y=6

3y/3=6/3

y=2.

substitute the given value of y into the equation

x=14-3y

x=14-3×2

x=14-6

x=8.

the possible solution of the system is the ordered pair (x,y)

(x,y)=(8,2)

x=8

Y=2

Proof:

Check if the given ordered pair is the solution of the system of equations

8+6×2=20

8+3×2=14

simply the equalities

20=20

14=14

since all of the equalities are true, the ordered pair is the solution of the system

(x,y)=(8,2)

xxTIMURxx [149]3 years ago

6 0

Answer:

x = 8, y = 2

Step-by-step explanation:

Multiply the second equation by -2:

x + 6y = 20

-2x - 6y = -28

Add the equations and simplify:

-x = -8

x = 8

Plug x = 8 back into the first equation and solve for y:

8 + 6y = 20

6y = 12

y = 2

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Dennis_Churaev [7]

Answer: Option D, the actual speed of the wind is 16km/h.

Step-by-step explanation:

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When the plane flies against the wind, the total speed will be:

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Then we have two equations:

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We want to find the speed of the wind, so we should isolate the speed of the plane in one of the equations, let's isolate it in the second equation:

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3 years ago

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BartSMP [9]

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3 years ago

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Pavlova-9 [17]

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Vsevolod [243]

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3 years ago

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Gnesinka [82]

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3 years ago