Question

Solve the system by the elimination method.

3x - 2y - 7 = 0
5x + y - 3 = 0
To eliminate y, the LCM is 2. Which of the following is the resulting equations?

Answer 1

10x + 2y - 6 = 0

Multiply 5x + y - 3 = 0 by 2

2(5x + y - 3 = 0) = 10x + 2y - 6 = 0

Answer 2

Answer: The resulting equation are,

3x - 2y - 7 = 0

10x + 2y - 6 = 0

Explanation:

Since, for solving a system of equations by the elimination method we either add or subtract the equations to get an equation in one variable.

For this we find out the L.C.M. of the coefficients of that variable which we want to eliminate.

Here, the given equations are,

3x - 2y - 7 = 0 -----(1)

5x + y - 3 = 0 -----(2)

For eliminating y,

The coefficient of y in equation (1) = 2,

And, the coefficient of y in equation (2) = 1

L.C.M. (2, 1) = 2,

Thus, we make 2 as the coefficient of y in both equations,

For this we multiply equation (2) by 2 and equation (1) by 1,

Resultant equations are,

3x - 2y - 7 = 0

10x + 2y - 6 = 0