SOLUTION: y=18x-9 -108x+6y=-54 Graph and describe consistent,dependent etc.

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Question 995177: y=18x-9
-108x+6y=-54
Graph and describe consistent,dependent etc.
Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.
system%28y=18x-9%2C%0D%0A-108x%2B6y=-54%29.

Rewrite it in the standard form

system%2818x+-+y+=+-9%2C%0D%0A-108x+%2B+6y+=+-54%29.

The rows of coefficients are proportional with the proportionality coefficient  -6  (or  -1%2F6).  The right side terms are proportional with the same coefficient.
Hence,  the equations are  dependent.  The straight lines that correspond to these equations are parallel.  Moreother,  they have the common point  (x,y) =  (0,-9)
and,  therefore, coincide.  Hence,  the system is  consistent.

See the lesson  Geometric interpretation of the linear system of two equations in two unknowns  in this site.