1. Elimination / AdditionWe eliminate one of the unknowns by adding or subtracting the equations.

2. Elimination / AdditionWe eliminate one of the unknowns by adding or subtracting the equations. To do so, sometimes we must multiply one or both equations by certain numbers until we have the same unknown with opposite coefficients. 3. Elimination / Addition For example:3x2y=1 x4y=19} 4. Elimination / Addition To get rid of the x, I have to multiply the second equation by 3.}3x2y=1 3x2y=1 x4y=19 3x12y=57} 5. Elimination / Addition We add now both sides of the equations separatedly:3x2y=1 3x12y=57}14y=56 56 y= 14 y=4 6. Elimination / Addition All that rests now is finding the value of x, plugging the value y=4 in either of the equations:x4y=19 x4 4=19 x=1916 x=3 7. Elimination / Addition The same example, now eliminating the y.3x2y=1 x4y=19} 8. Elimination / Addition The same example, now eliminating the y.3x2y=1 x4y=19}6x4y=2 x4y=19} 9. Elimination / Addition We add the equations:6x4y=2 x4y=19 7x=21 21 x= 7 x=3} 10. Elimination / Addition Now we just have to plug the value x=3 in either of the equations:x4y=19 34y=19 4y=193 16 y= 4 y=4