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Comment on Value of x in a System
How come you can't take one
Try it, and you'll find a
Try it, and you'll find a problem.
The reason you'll find a problem is that both equations are equivalent. That is, both equations can be written as 6x - 3y = -9 (or we could write both equations as 2x - y = -3).
So, we don't have two unique equations with 2 variable. Instead, we have ONE equation with 2 variables.
hi Brent, how did you know
I derived the same conclusion when I solved the solved both the equations for x and I got the same result. But your approach is faster.
Great question!
Great question!
Once we have....
4x - 2y = -6
6x - 3y = -9
.... I noticed that 6x = 1.5(4x) and 3y = 1.5(2y) and 9 = 1.5(6)
So, I knew that multiplying the top equation by 1.5 would yield equivalent equations.
If you divide statement 1 by