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Solve the systems of linear equations by graphing. State whether the system is consistent/inconsistent, dependent/independent. 12x - 9y = 27 and 8x - 6y = 18

User Geoffrey Hale
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We have the system of equations:

12x - 9y = 27

8x - 6y = 18

If we are going to solve the equation by graphing, we need to put these equations in the slope-intercept form:

y = m*x + b

Where m is the slope of the equation, and b is the intercept of the graph with the vertical line. For the first equation:

12x - 27 = 9y

Dividing by 9:

12x/9 - 27/9 = y

=> y = 4x/3 - 3 ...(1)

Now, for the second equation:

8x - 18 = 6y

Dividing by 6:

y = 4x/3 - 3 ...(2)

We can see that (1) and (2) are identical, so we conclude that the system of equations is consistent dependent (there are infinite solutions).

User Therealprashant
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