Question

in order to solve he following system of equations by subtraction, which of the following could you do before subtracting the equations so that one variable will be eliminated when you subtract them? 4x-2y=7, 3x-3y=15

Answer 1

To eliminate x multiply the first equation by 3 and the second equation by 4

To eliminate y multiply the first equation by 3 and the second equation by 2

Explanation:

We are given a system of linear equations;

4x-2y=7

3x-3y=15

solving by elimination means that we shall be getting rid of one of the variables in order to determine the other. In this case we can either eliminate x or y. In order to eliminate any of these variables, we first must make their coefficients equal in both equations. To eliminate x;

Multiply the first equation by 3 and the second equation by 4.

To eliminate y;

Multiply the first equation by 3 and the second equation by 2.