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WandaA
Feb 5, 2008, 06:11 PM
how do you solve this problem without using a calculator..

3x-6y=12
2x-4y=8

you have to write no solution or infinitely many solutions... its solving systems by graphing

SirOracle
Feb 5, 2008, 09:47 PM
if you divide both sides of the first equation by 3 and both sides of the second equation by 2, you get:

x - 2y = 4
x - 2y = 4

Since these are both the same line, there are infinitely many solutions. This could also be shown by plugging in any x value into both equations, as it would yield the same y value in each case. Graphing points on the line would also show that the lines are the same.