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anonnnn
I have to solve the system 7x - 3y = 20 5x + 3y = 16 I solved it once; 7x - 3y = 20 + 5x + 3y = 16 = 12x = 36 = x = 3 7(3) = 3y = 20 = 21 - 3y = 20 21 - 21 - 3y = 21 - 21 = 3y = -1 = y = 1/3 so (3, 1/3) But I cant figure out how to solve it for a nother way and get the same answer.
Example: 2X+6Y=10 3X-2Y=12 There is another method called substitution, in which you manipulate one of the equation to isolate a variable. For example 2X+6Y=10 can be manipulated into X=5-3Y Then you substitute the second part of the equation, 5-3Y in the second equation, 3X-2Y=12, resulting in 3(5-3Y)-2Y=12. Then you can use simple algebra to figure out X and Y
I know about substitution, and I have attempted it several times in several different manners but I cannot come up with the same answer as the first.
There's at least five different ways of solving these 1. Graphing 2. Substitution 3. Elimination 4. Matrices 5. Cramer's Method Pick one
There's also slope-intercept method as well