Chapter 6 - Systems of Equations and Inequalities - Concept Byte - Matrices and Solving Systems - Page 382: 4

The row operations used in the activity were the same as the operations used in the elimination method. The goal was to eliminate one variable. There are no differences between the two methods.

$3x+2y=11$ $4x+y=18$ $-2*(4x+y=18)$ $-8x-2y=-36$ $3x+2y=11$ $-8x-2y=-36$ $3x-8x+2y-2y=11-36$ $-5x = -25$ $-5x/-5 = -25/-5$ $x = 5$ $4x+y=18$ $4*5+y=18$ $20+y=18$ $y=-2$ $(5,-2)$