5c-Solving+by+elimination+(section+3.2)

Solving by Elimination (section 3.2)

To use if you need help:http://www.purplemath.com/modules/systlin5.htm

Here are some examples of using the elimination method when solving systems:

2x-6y=12 -8x+3y=-41 First make one variable the opposite of the other by multiplying:

4(2x) -4(6y) =4(12) 8x-24y=48 Now the two equations will have a variable that cancels out.Then take this equation and add it to the other:

8x-24y=48 + -8x+3y=-41 ____________ -21y=7 y=7/-21 y=-1/3 Now that you have found y, plug y into one of your original equations and find x:

2x-6(-1/3)=12 2x+6/3=12 2x+2=12 -2 -2 __________ 2x=10 x=10/2 x=5 Your answer is (5, 1/3)

Here is another example:

4x-2y=10 -6x+3y=8

3(4)x-3(2)y=3(10) and 2(-6)x+2(3)y=2(8)

12x-6y=30 +-12x+6y=16 _____________0 does not equal 46 Therefore the answer is no solution.