Posted by Nina on Saturday, July 25, 2009 at 2:39pm.
Determine the system which is equivalent to the system:
3x+4y=12
x2y=9
a)
3x+4y=12
3x6y=27
b)
3x+4y=12
2x4y=18
c)
10y=15
5x=30
d)
Any of A,B or C

Systems (maths)  Damon, Saturday, July 25, 2009 at 4:22pm
In b, the first equation is unchanged.
In b, the second equation is multiplied by 2, every term, so it is unchanged. 
Systems (maths)  MathMate, Saturday, July 25, 2009 at 5:20pm
In c, the values of x and y are explicit.
Substitute these values in A and B and see if they work.