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Solve the given system of differential equations by systematic elimination

dx/dt = 4x + 7y
dy/dt= x - 2y

User Mrinal
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1 Answer

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Final answer:

To solve the given system of differential equations by systematic elimination, multiply the first equation by 2 and the second equation by 7 to eliminate the y term. Then, subtract the second equation from the first equation to eliminate the y term. Finally, rearrange the equation to solve for y.

Step-by-step explanation:

To solve the given system of differential equations by systematic elimination, we can start by multiplying the first equation by 2 and the second equation by 7 to eliminate the y term. This gives us:

2(dx/dt) = 8x + 14y

7(dy/dt) = 7x - 14y

Next, we can subtract the second equation from the first equation to eliminate the y term:

2(dx/dt) - 7(dy/dt) = 8x + 14y - (7x - 14y)

2(dx/dt) - 7(dy/dt) = x + 21y

Finally, we can rearrange the equation to solve for y:

21(dy/dt) = 2(dx/dt) - x

dy/dt = (2/21)(dx/dt) - (1/21)x

So the solution to the system of differential equations is:

dx/dt = 4x + 7y

dy/dt = (2/21)(dx/dt) - (1/21)x

User Talkhabi
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