Find the value of Q in the following system so that the solution to the system is {(x, y): x - 3y = 4}?
x - 3y = 4 and Qx - 6y=8

Solution:

Given are the linear equations in two variables.  

x - 3y = 4 --- (1)

Qx - 6y = 8 --- (2)

Multiply equation (1) by 2

2x - 6y = 8

Subtract equation (1) and (2)

⇒ 2x - Qx = 0

Taking out the common terms

(2 - Q)x = 0

By further calculation

2 - Q = 0

So we get

Q = 2

Therefore, the value of Q is 2.

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Find the value of Q in the following system so that the solution to the system is {(x, y): x - 3y = 4} ?
x - 3y = 4 and Qx - 6y = 8

Summary:

The value of Q in the following system so that the solution to the system is {(x, y): x - 3y = 4}, x - 3y = 4 and Qx -6y = 8 is 2.